Merge remote-tracking branch 'upstream/dev/3.0.0'

# Conflicts:
#	proxy/src/main/java/com/velocitypowered/proxy/protocol/StateRegistry.java

.github/workflows/gradle.yml

@@ -6,18 +6,18 @@ on: [push, pull_request]
 
 jobs:
   build:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
     - name: Checkout Repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
       with:
         persist-credentials: false
     - name: Set up Gradle
-      uses: gradle/actions/setup-gradle@v4
-    - name: Set up JDK 17
-      uses: actions/setup-java@v4
+      uses: gradle/actions/setup-gradle@v5
+    - name: Set up JDK 21
+      uses: actions/setup-java@v5
       with:
-        java-version: 17
-        distribution: 'temurin'
+        java-version: 21
+        distribution: 'zulu'
     - name: Build with Gradle
       run: ./gradlew build

README.md

@@ -34,3 +34,9 @@ and you can configure it from there.
 
 Alternatively, you can get the proxy JAR from the [downloads](https://papermc.io/downloads/velocity)
 page.
+
+# Localisation
+
+Translations are handled using [Crowdin](https://papermc-io.crowdin.com/velocity).
+If you want to translate a language not available on Crowdin,
+you might want to ask in the [Discord](https://discord.gg/papermc) about it.

api/build.gradle.kts

@@ -59,18 +59,18 @@ tasks {
 
         val o = options as StandardJavadocDocletOptions
         o.encoding = "UTF-8"
-        o.source = "17"
+        o.source = "21"
 
         o.use()
         o.links(
-            "https://www.slf4j.org/apidocs/",
+            "https://www.javadocs.dev/org.slf4j/slf4j-api/${libs.slf4j.get().version}/",
             "https://guava.dev/releases/${libs.guava.get().version}/api/docs/",
             "https://google.github.io/guice/api-docs/${libs.guice.get().version}/javadoc/",
             "https://docs.oracle.com/en/java/javase/17/docs/api/",
             "https://jd.advntr.dev/api/${libs.adventure.bom.get().version}/",
             "https://jd.advntr.dev/text-minimessage/${libs.adventure.bom.get().version}/",
             "https://jd.advntr.dev/key/${libs.adventure.bom.get().version}/",
-            "https://javadoc.io/doc/com.github.ben-manes.caffeine/caffeine/${libs.caffeine.get().version}/",
+            "https://www.javadocs.dev/com.github.ben-manes.caffeine/caffeine/${libs.caffeine.get().version}/",
         )
 
         o.tags(

api/src/ap/java/com/velocitypowered/api/plugin/ap/PluginAnnotationProcessor.java

@@ -14,7 +14,6 @@ import com.velocitypowered.api.plugin.Plugin;
 import java.io.BufferedWriter;
 import java.io.IOException;
 import java.io.Writer;
-import java.util.Objects;
 import java.util.Set;
 import javax.annotation.processing.AbstractProcessor;
 import javax.annotation.processing.ProcessingEnvironment;
@@ -68,8 +67,8 @@ public class PluginAnnotationProcessor extends AbstractProcessor {
 
       Name qualifiedName = ((TypeElement) element).getQualifiedName();
 
-      if (Objects.equals(pluginClassFound, qualifiedName.toString())) {
-        if (!warnedAboutMultiplePlugins) {
+      if (pluginClassFound != null) {
+        if (!pluginClassFound.equals(qualifiedName.toString()) && !warnedAboutMultiplePlugins) {
           environment.getMessager()
               .printMessage(Diagnostic.Kind.WARNING, "Velocity does not yet currently support "
                   + "multiple plugins. We are using " + pluginClassFound

api/src/ap/java/com/velocitypowered/api/plugin/ap/SerializedPluginDescription.java

@@ -24,7 +24,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  */
 public final class SerializedPluginDescription {
 
-  public static final Pattern ID_PATTERN = Pattern.compile("[a-z][a-z0-9-_]{0,63}");
+  public static final String ID_PATTERN_STRING = "[a-z][a-z0-9-_]{0,63}";
+  public static final Pattern ID_PATTERN = Pattern.compile(ID_PATTERN_STRING);
 
   // @Nullable is used here to make GSON skip these in the serialized file
   private final String id;

api/src/main/java/com/velocitypowered/api/command/CommandSource.java

@@ -23,7 +23,7 @@ public interface CommandSource extends Audience, PermissionSubject {
    * Sends a message with the MiniMessage format to this source.
    *
    * @param message MiniMessage content
-   * @see <a href="https://docs.advntr.dev/minimessage/format.html">MiniMessage docs</a>
+   * @see <a href="https://docs.papermc.io/adventure/minimessage/format/">MiniMessage docs</a>
    *      for more information on the format.
    **/
   default void sendRichMessage(final @NotNull String message) {
@@ -31,14 +31,14 @@ public interface CommandSource extends Audience, PermissionSubject {
   }
 
   /**
-  * Sends a message with the MiniMessage format to this source.
-  *
-  * @param message MiniMessage content
-  * @param resolvers resolvers to use
-  * @see <a href="https://docs.advntr.dev/minimessage/">MiniMessage docs</a>
-  *     and <a href="https://docs.advntr.dev/minimessage/dynamic-replacements">MiniMessage Placeholders docs</a>
-  *     for more information on the format.
-  **/
+   * Sends a message with the MiniMessage format to this source.
+   *
+   * @param message MiniMessage content
+   * @param resolvers resolvers to use
+   * @see <a href="https://docs.papermc.io/adventure/minimessage/">MiniMessage docs</a>
+   *     and <a href="https://docs.papermc.io/adventure/minimessage/dynamic-replacements">MiniMessage Placeholders docs</a>
+   *     for more information on the format.
+   */
   default void sendRichMessage(
           final @NotNull String message,
           final @NotNull TagResolver @NotNull... resolvers

api/src/main/java/com/velocitypowered/api/event/EventManager.java

@@ -60,7 +60,8 @@ public interface EventManager {
    *
    * @param plugin the plugin to associate with the handler
    * @param eventClass the class for the event handler to register
-   * @param postOrder the relative order in which events should be posted to the handler
+   * @param postOrder the relative order in which events should be posted to the handler. The higher
+   *     the priority, the earlier the event handler will be called
    * @param handler the handler to register
    * @param <E> the event type to handle
    */

api/src/main/java/com/velocitypowered/api/event/connection/LoginEvent.java

@@ -11,6 +11,7 @@ import com.google.common.base.Preconditions;
 import com.velocitypowered.api.event.ResultedEvent;
 import com.velocitypowered.api.event.annotation.AwaitingEvent;
 import com.velocitypowered.api.proxy.Player;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * This event is fired once the player has been authenticated, but before they connect to a server.
@@ -22,10 +23,24 @@ import com.velocitypowered.api.proxy.Player;
 public final class LoginEvent implements ResultedEvent<ResultedEvent.ComponentResult> {
 
   private final Player player;
+  private final String serverIdHash;
   private ComponentResult result;
 
+  @Deprecated(forRemoval = true)
   public LoginEvent(Player player) {
+    this(player, null);
+  }
+
+  /**
+   * Constructs a new {@link LoginEvent}.
+   *
+   * @param player the player who has completed authentication
+   * @param serverIdHash the server ID hash sent to Mojang for authentication,
+   *                     or {@code null} if the connection is in offline-mode
+   */
+  public LoginEvent(Player player, @Nullable String serverIdHash) {
     this.player = Preconditions.checkNotNull(player, "player");
+    this.serverIdHash = serverIdHash;
     this.result = ComponentResult.allowed();
   }
 
@@ -33,6 +48,16 @@ public final class LoginEvent implements ResultedEvent<ResultedEvent.ComponentRe
     return player;
   }
 
+  /**
+   * Returns the server ID hash that was sent to Mojang to authenticate the player.
+   * If the connection was in offline-mode, this returns {@code null}.
+   *
+   * @return the server ID hash that was sent to Mojang to authenticate the player
+   */
+  public @Nullable String getServerIdHash() {
+    return serverIdHash;
+  }
+
   @Override
   public ComponentResult getResult() {
     return result;

api/src/main/java/com/velocitypowered/api/event/player/PlayerChannelUnregisterEvent.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2025 Velocity Contributors
+ *
+ * The Velocity API is licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in the api top-level directory.
+ */
+
+package com.velocitypowered.api.event.player;
+
+import com.google.common.base.Preconditions;
+import com.velocitypowered.api.proxy.Player;
+import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
+import java.util.List;
+
+/**
+ * This event is fired when a client ({@link Player}) sends a plugin message through the
+ * unregister channel. Velocity will not wait on this event to finish firing.
+ */
+public final class PlayerChannelUnregisterEvent {
+
+  private final Player player;
+  private final List<ChannelIdentifier> channels;
+
+  public PlayerChannelUnregisterEvent(Player player, List<ChannelIdentifier> channels) {
+    this.player = Preconditions.checkNotNull(player, "player");
+    this.channels = Preconditions.checkNotNull(channels, "channels");
+  }
+
+  public Player getPlayer() {
+    return player;
+  }
+
+  public List<ChannelIdentifier> getChannels() {
+    return channels;
+  }
+
+  @Override
+  public String toString() {
+    return "PlayerChannelUnregisterEvent{"
+            + "player=" + player
+            + ", channels=" + channels
+            + '}';
+  }
+}

api/src/main/java/com/velocitypowered/api/event/player/ServerPreConnectEvent.java

@@ -143,7 +143,7 @@ public final class ServerPreConnectEvent implements
      * is used, then {@link ConnectionRequestBuilder#connect()}'s result will have the status
      * {@link Status#CONNECTION_CANCELLED}.
      *
-     * @return a result to deny conneections
+     * @return a result to deny connections
      */
     public static ServerResult denied() {
       return DENIED;

api/src/main/java/com/velocitypowered/api/event/proxy/ProxyPreShutdownEvent.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2018-2025 Velocity Contributors
+ *
+ * The Velocity API is licensed under the terms of the MIT License. For more details,
+ * reference the LICENSE file in the api top-level directory.
+ */
+
+package com.velocitypowered.api.event.proxy;
+
+import com.google.common.annotations.Beta;
+import com.velocitypowered.api.event.annotation.AwaitingEvent;
+
+/**
+ * This event is fired by the proxy after it has stopped accepting new connections,
+ * but before players are disconnected.
+ * This is the last point at which you can interact with currently connected players,
+ * for example to transfer them to another proxy or perform other cleanup tasks.
+ *
+ * @implNote Velocity will wait for all event listeners to complete before disconnecting players,
+ *     but note that the event will time out after the configured value of the
+ *     <code>velocity.pre-shutdown-timeout</code> system property, default 10 seconds,
+ *     in seconds to prevent shutdown from hanging indefinitely
+ * @since 3.4.0
+ */
+@Beta
+@AwaitingEvent
+public final class ProxyPreShutdownEvent {
+
+  @Override
+  public String toString() {
+    return "ProxyPreShutdownEvent";
+  }
+}

api/src/main/java/com/velocitypowered/api/network/ProtocolVersion.java

@@ -91,7 +91,11 @@ public enum ProtocolVersion implements Ordered<ProtocolVersion> {
   MINECRAFT_1_21_2(768, "1.21.2", "1.21.3"),
   MINECRAFT_1_21_4(769, "1.21.4"),
   MINECRAFT_1_21_5(770, "1.21.5"),
-  MINECRAFT_1_21_6(771, "1.21.6");
+  MINECRAFT_1_21_6(771, "1.21.6"),
+  MINECRAFT_1_21_7(772, "1.21.7", "1.21.8"),
+  MINECRAFT_1_21_9(773, "1.21.9", "1.21.10"),
+  MINECRAFT_1_21_11(774, "1.21.11"),
+  MINECRAFT_26_1(775, "26.1", "26.1.1", "26.1.2");
 
   private static final int SNAPSHOT_BIT = 30;
 

api/src/main/java/com/velocitypowered/api/plugin/Dependency.java

@@ -7,9 +7,11 @@
 
 package com.velocitypowered.api.plugin;
 
+import com.velocitypowered.api.plugin.ap.SerializedPluginDescription;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
+import org.intellij.lang.annotations.Pattern;
 
 /**
  * Indicates that the {@link Plugin} depends on another plugin in order to enable.
@@ -24,6 +26,7 @@ public @interface Dependency {
    * @return The dependency plugin ID
    * @see Plugin#id()
    */
+  @Pattern(SerializedPluginDescription.ID_PATTERN_STRING)
   String id();
 
   /**

api/src/main/java/com/velocitypowered/api/plugin/Plugin.java

@@ -7,10 +7,12 @@
 
 package com.velocitypowered.api.plugin;
 
+import com.velocitypowered.api.plugin.ap.SerializedPluginDescription;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
+import org.intellij.lang.annotations.Pattern;
 
 /**
  * Annotation used to describe a Velocity plugin.
@@ -26,6 +28,7 @@ public @interface Plugin {
    *
    * @return the ID for this plugin
    */
+  @Pattern(SerializedPluginDescription.ID_PATTERN_STRING)
   String id();
 
   /**

api/src/main/java/com/velocitypowered/api/proxy/Player.java

@@ -29,6 +29,7 @@ import java.util.Locale;
 import java.util.Optional;
 import java.util.UUID;
 import java.util.function.UnaryOperator;
+import net.kyori.adventure.dialog.DialogLike;
 import net.kyori.adventure.identity.Identified;
 import net.kyori.adventure.inventory.Book;
 import net.kyori.adventure.key.Key;
@@ -38,6 +39,7 @@ import net.kyori.adventure.sound.SoundStop;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.event.HoverEvent;
 import net.kyori.adventure.text.event.HoverEventSource;
+import net.kyori.adventure.text.object.PlayerHeadObjectContents;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.NotNull;
 
@@ -48,7 +50,8 @@ public interface Player extends
     /* Fundamental Velocity interfaces */
     CommandSource, InboundConnection, ChannelMessageSource, ChannelMessageSink,
     /* Adventure-specific interfaces */
-    Identified, HoverEventSource<HoverEvent.ShowEntity>, Keyed, KeyIdentifiable {
+    Identified, HoverEventSource<HoverEvent.ShowEntity>, Keyed, KeyIdentifiable, Sound.Emitter,
+    PlayerHeadObjectContents.SkinSource {
 
   /**
    * Returns the player's current username.
@@ -335,6 +338,15 @@ public interface Player extends
             Component.text(getUsername()))));
   }
 
+  @SuppressWarnings("UnstableApiUsage") // permitted implementation
+  @Override
+  default void applySkinToPlayerHeadContents(
+      final PlayerHeadObjectContents.@NotNull Builder builder) {
+    builder.skin(this.getGameProfile());
+    if (this.hasSentPlayerSettings()) {
+      builder.hat(this.getPlayerSettings().getSkinParts().hasHat());
+    }
+  }
 
   /**
    * Gets the player's client brand.
@@ -383,8 +395,12 @@ public interface Player extends
   /**
    * {@inheritDoc}
    *
-   * <b>This method is not currently implemented in Velocity
-   * and will not perform any actions.</b>
+   *
+   * @apiNote <b>This method is not currently implemented in Velocity
+   *     and will not perform any actions.</b>
+   * @see #playSound(Sound, Sound.Emitter)
+   * @see <a href="https://docs.papermc.io/velocity/dev/pitfalls/#audience-operations-are-not-fully-supported">
+   *   Unsupported Adventure Operations</a>
    */
   @Override
   default void playSound(@NotNull Sound sound) {
@@ -393,8 +409,11 @@ public interface Player extends
   /**
    * {@inheritDoc}
    *
-   * <b>This method is not currently implemented in Velocity
-   * and will not perform any actions.</b>
+   * @apiNote <b>This method is not currently implemented in Velocity
+   *     and will not perform any actions.</b>
+   * @see #playSound(Sound, Sound.Emitter)
+   * @see <a href="https://docs.papermc.io/velocity/dev/pitfalls/#audience-operations-are-not-fully-supported">
+   *   Unsupported Adventure Operations</a>
    */
   @Override
   default void playSound(@NotNull Sound sound, double x, double y, double z) {
@@ -403,18 +422,28 @@ public interface Player extends
   /**
    * {@inheritDoc}
    *
-   * <b>This method is not currently implemented in Velocity
-   * and will not perform any actions.</b>
+   * <p><b>Note</b>: Due to <a href="https://bugs.mojang.com/browse/MC/issues/MC-146721">MC-146721</a>, stereo sounds are always played globally in 1.14+.
+   *
+   * <p><b>Note</b>: Due to <a href="https://bugs.mojang.com/browse/MC/issues/MC-138832">MC-138832</a>, the volume and pitch are ignored when using this method in 1.14 to 1.16.5.
+   *
+   * @param sound the sound to play
+   * @param emitter the emitter of the sound; may be another player of this player's server
+   * @since 3.4.0
+   * @sinceMinecraft 1.19.3
+   * @apiNote This method is currently only implemented for players on 1.19.3+
+   *     and requires a present {@link #getCurrentServer} for the emitting player as well as this player.
    */
   @Override
-  default void playSound(@NotNull Sound sound, Sound.Emitter emitter) {
+  default void playSound(@NotNull Sound sound, @NotNull Sound.Emitter emitter) {
   }
 
   /**
    * {@inheritDoc}
    *
-   * <b>This method is not currently implemented in Velocity
-   * and will not perform any actions.</b>
+   * @param stop the sound and/or a sound source, to stop
+   * @since 3.4.0
+   * @sinceMinecraft 1.19.3
+   * @apiNote This method is currently only implemented for players on 1.19.3+.
    */
   @Override
   default void stopSound(@NotNull SoundStop stop) {
@@ -425,11 +454,40 @@ public interface Player extends
    *
    * <b>This method is not currently implemented in Velocity
    * and will not perform any actions.</b>
+   *
+   * @see <a href="https://docs.papermc.io/velocity/dev/pitfalls/#audience-operations-are-not-fully-supported">
+   *   Unsupported Adventure Operations</a>
    */
   @Override
   default void openBook(@NotNull Book book) {
   }
 
+  /**
+   * {@inheritDoc}
+   *
+   * <b>This method is not currently implemented in Velocity
+   * and will not perform any actions.</b>
+   *
+   * @see <a href="https://docs.papermc.io/velocity/dev/pitfalls/#audience-operations-are-not-fully-supported">
+   *   Unsupported Adventure Operations</a>
+   */
+  @Override
+  default void showDialog(@NotNull DialogLike dialog) {
+  }
+
+  /**
+   * {@inheritDoc}
+   *
+   * <b>This method is not currently implemented in Velocity
+   * and will not perform any actions.</b>
+   *
+   * @see <a href="https://docs.papermc.io/velocity/dev/pitfalls/#audience-operations-are-not-fully-supported">
+   *   Unsupported Adventure Operations</a>
+   */
+  @Override
+  default void closeDialog() {
+  }
+
   /**
    * Transfers a Player to a host.
    *

api/src/main/java/com/velocitypowered/api/proxy/server/ServerPing.java

@@ -19,7 +19,9 @@ import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.UUID;
-import org.checkerframework.checker.nullness.qual.Nullable;
+import net.kyori.adventure.text.Component;
+import org.jspecify.annotations.Nullable;
+
 
 /**
  * Represents a 1.7 and above server list ping response. This class is immutable.
@@ -28,9 +30,10 @@ public final class ServerPing {
 
   private final Version version;
   private final @Nullable Players players;
-  private final net.kyori.adventure.text.Component description;
+  private final @Nullable Component description;
   private final @Nullable Favicon favicon;
   private final @Nullable ModInfo modinfo;
+  private final boolean preventsChatReports = true;
 
   public ServerPing(Version version, @Nullable Players players,
       net.kyori.adventure.text.Component description, @Nullable Favicon favicon) {
@@ -47,8 +50,8 @@ public final class ServerPing {
    * @param modinfo the mods this server runs
    */
   public ServerPing(Version version, @Nullable Players players,
-      net.kyori.adventure.text.Component description, @Nullable Favicon favicon,
-      @Nullable ModInfo modinfo) {
+                    Component description, @Nullable Favicon favicon,
+                    @Nullable ModInfo modinfo) {
     this.version = Preconditions.checkNotNull(version, "version");
     this.players = players;
     this.description = Preconditions.checkNotNull(description, "description");
@@ -64,7 +67,8 @@ public final class ServerPing {
     return Optional.ofNullable(players);
   }
 
-  public net.kyori.adventure.text.Component getDescriptionComponent() {
+  @Nullable
+  public Component getDescriptionComponent() {
     return description;
   }
 
@@ -151,7 +155,7 @@ public final class ServerPing {
     private final List<SamplePlayer> samplePlayers = new ArrayList<>();
     private String modType = "FML";
     private final List<ModInfo.Mod> mods = new ArrayList<>();
-    private net.kyori.adventure.text.Component description;
+    private Component description;
     private @Nullable Favicon favicon;
     private boolean nullOutPlayers;
     private boolean nullOutModinfo;
@@ -299,7 +303,7 @@ public final class ServerPing {
      * @param description Component to use as the description.
      * @return this builder, for chaining
      */
-    public Builder description(net.kyori.adventure.text.Component description) {
+    public Builder description(Component description) {
       this.description = Preconditions.checkNotNull(description, "description");
       return this;
     }
@@ -359,7 +363,7 @@ public final class ServerPing {
       return samplePlayers;
     }
 
-    public Optional<net.kyori.adventure.text.Component> getDescriptionComponent() {
+    public Optional<Component> getDescriptionComponent() {
       return Optional.ofNullable(description);
     }
 

api/src/main/java/com/velocitypowered/api/util/GameProfile.java

@@ -11,11 +11,14 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.UUID;
+import java.util.stream.Collectors;
+import net.kyori.adventure.text.object.PlayerHeadObjectContents;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Represents a Mojang game profile. This class is immutable.
  */
-public final class GameProfile {
+public final class GameProfile implements PlayerHeadObjectContents.SkinSource {
 
   private final UUID id;
   private final String undashedId;
@@ -169,6 +172,23 @@ public final class GameProfile {
         ImmutableList.of());
   }
 
+  @SuppressWarnings("UnstableApiUsage") // permitted implementation
+  @Override
+  public void applySkinToPlayerHeadContents(
+      final PlayerHeadObjectContents.@NotNull Builder builder) {
+    if (this.properties.isEmpty()) {
+      builder.id(this.id);
+      return;
+    }
+
+    builder.id(this.id)
+        .name(this.name)
+        .profileProperties(this.properties.stream()
+            .map(property -> PlayerHeadObjectContents.property(property.getName(),
+                property.getValue(), property.getSignature()))
+            .collect(Collectors.toList()));
+  }
+
   @Override
   public String toString() {
     return "GameProfile{"

build-logic/src/main/kotlin/velocity-init-manifest.gradle.kts

@@ -2,8 +2,15 @@ import org.gradle.jvm.tasks.Jar
 import org.gradle.kotlin.dsl.withType
 import java.io.ByteArrayOutputStream
 
+// This interface is needed as a workaround to get an instance of ExecOperations
+interface Injected {
+    @get:Inject
+    val execOps: ExecOperations
+}
+
 val currentShortRevision = ByteArrayOutputStream().use {
-    exec {
+    val execOps = objects.newInstance<Injected>().execOps
+    execOps.exec {
         executable = "git"
         args = listOf("rev-parse", "HEAD")
         standardOutput = it

build-logic/src/main/kotlin/velocity-publish.gradle.kts

@@ -8,10 +8,10 @@ extensions.configure<PublishingExtension> {
         maven {
             credentials(PasswordCredentials::class.java)
 
-            name = "paper"
-            val base = "https://repo.papermc.io/repository/maven"
-            val releasesRepoUrl = "$base-releases/"
-            val snapshotsRepoUrl = "$base-snapshots/"
+            name = if (version.toString().endsWith("SNAPSHOT")) "paperSnapshots" else "paper" // "paper" is seemingly not defined
+            val base = "https://artifactory.papermc.io/artifactory"
+            val releasesRepoUrl = "$base/releases/"
+            val snapshotsRepoUrl = "$base/snapshots/"
             setUrl(if (version.toString().endsWith("SNAPSHOT")) snapshotsRepoUrl else releasesRepoUrl)
         }
     }

build.gradle.kts

@@ -12,7 +12,7 @@ subprojects {
 
     java {
         toolchain {
-            languageVersion.set(JavaLanguageVersion.of(17))
+            languageVersion.set(JavaLanguageVersion.of(21))
         }
     }
 
@@ -20,11 +20,11 @@ subprojects {
         testImplementation(rootProject.libs.junit)
     }
 
-    tasks {
-        test {
-            useJUnitPlatform()
-            reports {
-                junitXml.required.set(true)
+    testing.suites.named<JvmTestSuite>("test") {
+        useJUnitJupiter()
+        targets.all {
+            testTask.configure {
+                reports.junitXml.required = true
             }
         }
     }

gradle.properties

@@ -1,2 +1,2 @@
 group=com.velocitypowered
-version=3.4.0-SNAPSHOT
+version=3.5.0-SNAPSHOT

gradle/libs.versions.toml

@@ -1,26 +1,26 @@
 [versions]
 configurate3 = "3.7.3"
-configurate4 = "4.1.2"
+configurate4 = "4.2.0"
 flare = "2.0.1"
-log4j = "2.24.3"
-netty = "4.2.1.Final"
+log4j = "2.25.3"
+netty = "4.2.10.Final"
 
 [plugins]
-indra-publishing = "net.kyori.indra.publishing:2.0.6"
-shadow = "io.github.goooler.shadow:8.1.5"
-spotless = "com.diffplug.spotless:6.25.0"
+fill = "io.papermc.fill.gradle:1.0.10"
+shadow = "com.gradleup.shadow:9.3.1"
+spotless = "com.diffplug.spotless:8.2.0"
 
 [libraries]
-adventure-bom = "net.kyori:adventure-bom:4.21.0"
-adventure-text-serializer-json-legacy-impl = "net.kyori:adventure-text-serializer-json-legacy-impl:4.21.0"
-adventure-facet = "net.kyori:adventure-platform-facet:4.3.4"
-asm = "org.ow2.asm:asm:9.8"
-auto-service = "com.google.auto.service:auto-service:1.0.1"
-auto-service-annotations = "com.google.auto.service:auto-service-annotations:1.0.1"
+adventure-bom = "net.kyori:adventure-bom:4.26.1"
+adventure-text-serializer-json-legacy-impl = "net.kyori:adventure-text-serializer-json-legacy-impl:4.26.1"
+adventure-facet = "net.kyori:adventure-platform-facet:4.4.1"
+asm = "org.ow2.asm:asm:9.9.1"
+auto-service = "com.google.auto.service:auto-service:1.1.1"
+auto-service-annotations = "com.google.auto.service:auto-service-annotations:1.1.1"
 brigadier = "com.velocitypowered:velocity-brigadier:1.0.0-SNAPSHOT"
-bstats = "org.bstats:bstats-base:3.0.3"
-caffeine = "com.github.ben-manes.caffeine:caffeine:3.1.8"
-checker-qual = "org.checkerframework:checker-qual:3.42.0"
+bstats = "org.bstats:bstats-base:3.1.0"
+caffeine = "com.github.ben-manes.caffeine:caffeine:3.2.3"
+checker-qual = "org.checkerframework:checker-qual:3.53.0"
 checkstyle = "com.puppycrawl.tools:checkstyle:10.9.3"
 completablefutures = "com.spotify:completable-futures:0.3.6"
 configurate3-hocon = { module = "org.spongepowered:configurate-hocon", version.ref = "configurate3" }
@@ -33,21 +33,21 @@ disruptor = "com.lmax:disruptor:4.0.0"
 fastutil = "it.unimi.dsi:fastutil:8.5.15"
 flare-core = { module = "space.vectrix.flare:flare", version.ref = "flare" }
 flare-fastutil = { module = "space.vectrix.flare:flare-fastutil", version.ref = "flare" }
-jline = "org.jline:jline-terminal-jansi:3.30.2"
+jline = "org.jline:jline-terminal-jansi:3.30.6"
 jopt = "net.sf.jopt-simple:jopt-simple:5.0.4"
-junit = "org.junit.jupiter:junit-jupiter:5.10.2"
-jspecify = "org.jspecify:jspecify:0.3.0"
+junit = "org.junit.jupiter:junit-jupiter:5.14.2"
+jspecify = "org.jspecify:jspecify:1.0.0"
 kyori-ansi = "net.kyori:ansi:1.1.1"
-guava = "com.google.guava:guava:25.1-jre"
-gson = "com.google.code.gson:gson:2.10.1"
-guice = "com.google.inject:guice:6.0.0"
+guava = "com.google.guava:guava:33.5.0-jre"
+gson = "com.google.code.gson:gson:2.13.2"
+guice = "com.google.inject:guice:7.0.0"
 lmbda = "org.lanternpowered:lmbda:2.0.0"
 log4j-api = { module = "org.apache.logging.log4j:log4j-api", version.ref = "log4j" }
 log4j-core = { module = "org.apache.logging.log4j:log4j-core", version.ref = "log4j" }
 log4j-slf4j-impl = { module = "org.apache.logging.log4j:log4j-slf4j2-impl", version.ref = "log4j" }
 log4j-iostreams = { module = "org.apache.logging.log4j:log4j-iostreams", version.ref = "log4j" }
 log4j-jul = { module = "org.apache.logging.log4j:log4j-jul", version.ref = "log4j" }
-mockito = "org.mockito:mockito-core:5.10.0"
+mockito = "org.mockito:mockito-core:5.21.0"
 netty-codec = { module = "io.netty:netty-codec", version.ref = "netty" }
 netty-codec-haproxy = { module = "io.netty:netty-codec-haproxy", version.ref = "netty" }
 netty-codec-http = { module = "io.netty:netty-codec-http", version.ref = "netty" }
@@ -55,10 +55,10 @@ netty-handler = { module = "io.netty:netty-handler", version.ref = "netty" }
 netty-transport-native-epoll = { module = "io.netty:netty-transport-native-epoll", version.ref = "netty" }
 netty-transport-native-kqueue = { module = "io.netty:netty-transport-native-kqueue", version.ref = "netty" }
 netty-transport-native-iouring = { module = "io.netty:netty-transport-native-io_uring", version.ref = "netty" }
-nightconfig = "com.electronwill.night-config:toml:3.6.7"
+nightconfig = "com.electronwill.night-config:toml:3.8.3"
 slf4j = "org.slf4j:slf4j-api:2.0.17"
-snakeyaml = "org.yaml:snakeyaml:1.33"
-spotbugs-annotations = "com.github.spotbugs:spotbugs-annotations:4.7.3"
+snakeyaml = "org.yaml:snakeyaml:2.5"
+spotbugs-annotations = "com.github.spotbugs:spotbugs-annotations:4.9.8"
 terminalconsoleappender = "net.minecrell:terminalconsoleappender:1.3.0"
 
 [bundles]

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.11.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.3.0-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

gradlew

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 #
-# Copyright © 2015-2021 the original authors.
+# Copyright © 2015 the original authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -86,8 +86,7 @@ done
 # shellcheck disable=SC2034
 APP_BASE_NAME=${0##*/}
 # Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
-APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s
-' "$PWD" ) || exit
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -115,7 +114,6 @@ case "$( uname )" in                #(
   NONSTOP* )        nonstop=true ;;
 esac
 
-CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
 
 
 # Determine the Java command to use to start the JVM.
@@ -173,7 +171,6 @@ fi
 # For Cygwin or MSYS, switch paths to Windows format before running java
 if "$cygwin" || "$msys" ; then
     APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
-    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
 
     JAVACMD=$( cygpath --unix "$JAVACMD" )
 
@@ -203,18 +200,17 @@ fi
 
 
 # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-DEFAULT_JVM_OPTS='-Dfile.encoding=UTF-8 "-Xmx64m" "-Xms64m"'
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Collect all arguments for the java command:
-#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
 #     and any embedded shellness will be escaped.
 #   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
 #     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
-        -classpath "$CLASSPATH" \
-        org.gradle.wrapper.GradleWrapperMain \
+        -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
         "$@"
 
 # Stop when "xargs" is not available.
@@ -249,4 +245,4 @@ eval "set -- $(
         tr '\n' ' '
     )" '"$@"'
 
-exec "$JAVACMD" "$@"
+exec "$JAVACMD" "$@"

gradlew.bat

@@ -36,7 +36,7 @@ set APP_HOME=%DIRNAME%
 for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
 
 @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-set DEFAULT_JVM_OPTS=-Dfile.encoding=UTF-8 "-Xmx64m" "-Xms64m"
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
 
 @rem Find java.exe
 if defined JAVA_HOME goto findJavaFromJavaHome
@@ -70,11 +70,10 @@ goto fail
 :execute
 @rem Setup the command line
 
-set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 
 @rem Execute Gradle
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
 
 :end
 @rem End local scope for the variables with windows NT shell
@@ -91,4 +90,4 @@ exit /b %EXIT_CODE%
 :mainEnd
 if "%OS%"=="Windows_NT" endlocal
 
-:omega
+:omega

proxy/build.gradle.kts

@@ -1,14 +1,16 @@
 import com.github.jengelman.gradle.plugins.shadow.transformers.Log4j2PluginsCacheFileTransformer
+import io.papermc.fill.model.BuildChannel
 
 plugins {
     application
     id("velocity-init-manifest")
     alias(libs.plugins.shadow)
+    alias(libs.plugins.fill)
 }
 
 application {
     mainClass.set("com.velocitypowered.proxy.Velocity")
-    applicationDefaultJvmArgs += listOf("-Dvelocity.packet-decode-logging=true");
+    applicationDefaultJvmArgs += listOf("-Dvelocity.packet-decode-logging=true")
 }
 
 tasks {
@@ -25,6 +27,10 @@ tasks {
     }
 
     shadowJar {
+        filesMatching("META-INF/org/apache/logging/log4j/core/config/plugins/**") {
+            duplicatesStrategy = DuplicatesStrategy.INCLUDE
+        }
+
         transform(Log4j2PluginsCacheFileTransformer::class.java)
 
         // Exclude all the collection types we don"t intend to use
@@ -108,10 +114,27 @@ tasks {
     }
 }
 
+val projectVersion = version as String
+fill {
+    project("velocity")
+
+    build {
+        channel = BuildChannel.STABLE
+        versionFamily("3.0.0")
+        version(projectVersion)
+
+        downloads {
+            register("server:default") {
+                file = tasks.shadowJar.flatMap { it.archiveFile }
+                nameResolver.set { project, _, version, build -> "$project-$version-$build.jar" }
+            }
+        }
+    }
+}
+
 dependencies {
     implementation(project(":velocity-api"))
     implementation(project(":velocity-native"))
-    implementation(project(":velocity-proxy-log4j2-plugin"))
 
     implementation(libs.bundles.log4j)
     implementation(libs.kyori.ansi)
@@ -148,4 +171,5 @@ dependencies {
     testImplementation(libs.mockito)
 
     annotationProcessor(libs.auto.service)
+    annotationProcessor(libs.log4j.core)
 }

proxy/log4j2-plugin/build.gradle.kts

@@ -1,4 +0,0 @@
-dependencies {
-    implementation(libs.bundles.log4j)
-    annotationProcessor(libs.log4j.core)
-}

proxy/src/main/java/com/velocitypowered/proxy/Velocity.java

@@ -47,11 +47,6 @@ public class Velocity {
       System.setProperty("io.netty.native.workdir", System.getProperty("velocity.natives-tmpdir"));
     }
 
-    // Restore allocator used before Netty 4.2 due to oom issues with the adaptive allocator
-    if (System.getProperty("io.netty.allocator.type") == null) {
-      System.setProperty("io.netty.allocator.type", "pooled");
-    }
-
     // Disable the resource leak detector by default as it reduces performance. Allow the user to
     // override this if desired.
     if (!VelocityProperties.hasProperty("io.netty.leakDetection.level")) {

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -24,6 +24,7 @@ import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.velocitypowered.api.command.BrigadierCommand;
 import com.velocitypowered.api.event.proxy.ProxyInitializeEvent;
+import com.velocitypowered.api.event.proxy.ProxyPreShutdownEvent;
 import com.velocitypowered.api.event.proxy.ProxyReloadEvent;
 import com.velocitypowered.api.event.proxy.ProxyShutdownEvent;
 import com.velocitypowered.api.network.ProtocolVersion;
@@ -81,7 +82,6 @@ import java.net.http.HttpClient;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.security.KeyPair;
-import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -104,8 +104,8 @@ import net.kyori.adventure.audience.Audience;
 import net.kyori.adventure.audience.ForwardingAudience;
 import net.kyori.adventure.key.Key;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.minimessage.translation.MiniMessageTranslationStore;
 import net.kyori.adventure.translation.GlobalTranslator;
-import net.kyori.adventure.translation.TranslationStore;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.bstats.MetricsBase;
@@ -119,7 +119,7 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  */
 public class VelocityServer implements ProxyServer, ForwardingAudience {
 
-  public static final String VELOCITY_URL = "https://velocitypowered.com";
+  public static final String VELOCITY_URL = "https://papermc.io/software/velocity";
 
   private static final Logger logger = LogManager.getLogger(VelocityServer.class);
   public static final Gson GENERAL_GSON = new GsonBuilder()
@@ -150,6 +150,8 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
       )
       .registerTypeHierarchyAdapter(Favicon.class, FaviconSerializer.INSTANCE)
       .create();
+  private static final int PRE_SHUTDOWN_TIMEOUT =
+            Integer.getInteger("velocity.pre-shutdown-timeout", 10);
 
   private final ConnectionManager cm;
   private final ProxyOptions options;
@@ -216,7 +218,8 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
     ProxyVersion version = getVersion();
     PluginDescription description = new VelocityPluginDescription(
         "velocity", version.getName(), version.getVersion(), "The Velocity proxy",
-        VELOCITY_URL, ImmutableList.of(version.getVendor()), Collections.emptyList(), null);
+            version.getName().equals("Velocity") ? VELOCITY_URL : null,
+            ImmutableList.of(version.getVendor()), Collections.emptyList(), null);
     VelocityPluginContainer container = new VelocityPluginContainer(description);
     container.setInstance(VelocityVirtualPlugin.INSTANCE);
     return container;
@@ -238,8 +241,6 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
     console.setupStreams();
     pluginManager.registerPlugin(this.createVirtualPlugin());
 
-    registerTranslations();
-
     // Yes, you're reading that correctly. We're generating a 1024-bit RSA keypair. Sounds
     // dangerous, right? We're well within the realm of factoring such a key...
     //
@@ -288,6 +289,8 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
 
     this.doStartupConfigLoad();
 
+    registerTranslations();
+
     for (ServerInfo cliServer : options.getServers()) {
       servers.register(cliServer);
     }
@@ -338,8 +341,8 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
   }
 
   private void registerTranslations() {
-    final TranslationStore.StringBased<MessageFormat> translationRegistry =
-            TranslationStore.messageFormat(Key.key("velocity", "translations"));
+    final MiniMessageTranslationStore translationRegistry =
+            MiniMessageTranslationStore.create(Key.key("velocity", "translations"));
     translationRegistry.defaultLocale(Locale.US);
     try {
       ResourceUtils.visitResources(VelocityServer.class, path -> {
@@ -578,6 +581,20 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
       // done first to refuse new connections
       cm.shutdown();
 
+      try {
+        eventManager.fire(new ProxyPreShutdownEvent())
+                .toCompletableFuture()
+                .get(PRE_SHUTDOWN_TIMEOUT, TimeUnit.SECONDS);
+      } catch (TimeoutException ignored) {
+        logger.warn("Your plugins took over {} seconds during pre shutdown.",
+                PRE_SHUTDOWN_TIMEOUT);
+      } catch (ExecutionException ee) {
+        logger.error("Exception in ProxyPreShutdownEvent handler; continuing shutdown.", ee);
+      } catch (InterruptedException ignored) {
+        Thread.currentThread().interrupt();
+        logger.warn("Interrupted while waiting for ProxyPreShutdownEvent; continuing shutdown.");
+      }
+
       ImmutableList<ConnectedPlayer> players = ImmutableList.copyOf(connectionsByUuid.values());
       for (ConnectedPlayer player : players) {
         player.disconnect(reason);
@@ -817,7 +834,7 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
   public VelocityChannelRegistrar getChannelRegistrar() {
     return channelRegistrar;
   }
-  
+
   @Override
   public boolean isShuttingDown() {
     return shutdownInProgress.get();

proxy/src/main/java/com/velocitypowered/proxy/adventure/VelocityBossBarImplementation.java

@@ -53,15 +53,23 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
           viewer.getProtocolVersion(),
           viewer.translateMessage(this.bar.name())
       );
-      viewer.getConnection().write(BossBarPacket.createAddPacket(this.id, this.bar, name));
+      viewer.getBossBarManager().writeUpdate(this, BossBarPacket.createAddPacket(this.id, this.bar, name));
       return true;
     }
     return false;
   }
 
+  public void createDirect(final ConnectedPlayer viewer) {
+    final ComponentHolder name = new ComponentHolder(
+        viewer.getProtocolVersion(),
+        viewer.translateMessage(this.bar.name())
+    );
+    viewer.getConnection().write(BossBarPacket.createAddPacket(this.id, this.bar, name));
+  }
+
   public boolean viewerRemove(final ConnectedPlayer viewer) {
     if (this.viewers.remove(viewer)) {
-      viewer.getConnection().write(BossBarPacket.createRemovePacket(this.id, this.bar));
+      viewer.getBossBarManager().remove(this, BossBarPacket.createRemovePacket(this.id, this.bar));
       return true;
     }
     return false;
@@ -84,7 +92,7 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
           this.bar,
           new ComponentHolder(viewer.getProtocolVersion(), translated)
       );
-      viewer.getConnection().write(packet);
+      viewer.getBossBarManager().writeUpdate(this, packet);
     }
   }
 
@@ -96,7 +104,7 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
   ) {
     final BossBarPacket packet = BossBarPacket.createUpdateProgressPacket(this.id, this.bar);
     for (final ConnectedPlayer viewer : this.viewers) {
-      viewer.getConnection().write(packet);
+      viewer.getBossBarManager().writeUpdate(this, packet);
     }
   }
 
@@ -108,7 +116,7 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
   ) {
     final BossBarPacket packet = BossBarPacket.createUpdateStylePacket(this.id, this.bar);
     for (final ConnectedPlayer viewer : this.viewers) {
-      viewer.getConnection().write(packet);
+      viewer.getBossBarManager().writeUpdate(this, packet);
     }
   }
 
@@ -120,7 +128,7 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
   ) {
     final BossBarPacket packet = BossBarPacket.createUpdateStylePacket(this.id, this.bar);
     for (final ConnectedPlayer viewer : this.viewers) {
-      viewer.getConnection().write(packet);
+      viewer.getBossBarManager().writeUpdate(this, packet);
     }
   }
 
@@ -132,7 +140,7 @@ public final class VelocityBossBarImplementation implements BossBar.Listener,
   ) {
     final BossBarPacket packet = BossBarPacket.createUpdatePropertiesPacket(this.id, this.bar);
     for (final ConnectedPlayer viewer : this.viewers) {
-      viewer.getConnection().write(packet);
+      viewer.getBossBarManager().writeUpdate(this, packet);
     }
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/SuggestionsProvider.java

@@ -344,7 +344,7 @@ final class SuggestionsProvider<S> {
           return 0;
         });
       }
-      return potentials.get(0);
+      return potentials.getFirst();
     }
     return new ParseResults<>(contextSoFar, originalReader, Collections.emptyMap());
   }

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommandManager.java

@@ -35,7 +35,6 @@ import com.velocitypowered.api.command.CommandManager;
 import com.velocitypowered.api.command.CommandMeta;
 import com.velocitypowered.api.command.CommandResult;
 import com.velocitypowered.api.command.CommandSource;
-import com.velocitypowered.api.command.VelocityBrigadierMessage;
 import com.velocitypowered.api.event.command.CommandExecuteEvent;
 import com.velocitypowered.api.event.command.PostCommandInvocationEvent;
 import com.velocitypowered.api.plugin.PluginManager;
@@ -59,6 +58,7 @@ import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.stream.Collectors;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.ComponentLike;
 import net.kyori.adventure.text.format.NamedTextColor;
 import org.checkerframework.checker.lock.qual.GuardedBy;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -140,7 +140,7 @@ public class VelocityCommandManager implements CommandManager {
               command + " implements multiple registrable Command subinterfaces: "
                       + implementedInterfaces);
     } else {
-      this.internalRegister(commandRegistrars.get(0), command, meta);
+      this.internalRegister(commandRegistrars.getFirst(), command, meta);
     }
   }
 
@@ -242,8 +242,8 @@ public class VelocityCommandManager implements CommandManager {
           CommandSyntaxException.BUILT_IN_EXCEPTIONS.dispatcherUnknownCommand());
       if (isSyntaxError) {
         final Message message = e.getRawMessage();
-        if (message instanceof VelocityBrigadierMessage velocityMessage) {
-          source.sendMessage(velocityMessage.asComponent().applyFallbackStyle(NamedTextColor.RED));
+        if (message instanceof ComponentLike componentLike) {
+          source.sendMessage(componentLike.asComponent().applyFallbackStyle(NamedTextColor.RED));
         } else {
           source.sendMessage(Component.text(e.getMessage(), NamedTextColor.RED));
         }
@@ -256,7 +256,7 @@ public class VelocityCommandManager implements CommandManager {
       }
     } catch (final Throwable e) {
       // Ugly, ugly swallowing of everything Throwable, because plugins are naughty.
-      throw new RuntimeException("Unable to invoke command  " + parsed.getReader().getString() + "for " + source, e);
+      throw new RuntimeException("Unable to invoke command " + parsed.getReader().getString() + " for " + source, e);
     } finally {
       eventManager.fireAndForget(new PostCommandInvocationEvent(source, parsed.getReader().getString(), result));
     }
@@ -400,4 +400,4 @@ public class VelocityCommandManager implements CommandManager {
       return MoreExecutors.directExecutor();
     }
   }
-}
+}

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommands.java

@@ -70,33 +70,34 @@ public final class VelocityCommands {
       maybeCommand = VelocityBrigadierCommandWrapper.wrap(delegate.getCommand(), registrant);
     }
 
-    if (delegate instanceof LiteralCommandNode<CommandSource> lcn) {
-      var literalBuilder = shallowCopyAsBuilder(lcn, delegate.getName(), true);
-      literalBuilder.executes(maybeCommand);
-      // we also need to wrap any children
-      for (final CommandNode<CommandSource> child : delegate.getChildren()) {
-        literalBuilder.then(wrap(child, registrant));
+    return switch (delegate) {
+      case LiteralCommandNode<CommandSource> lcn -> {
+        var literalBuilder = shallowCopyAsBuilder(lcn, delegate.getName(), true);
+        literalBuilder.executes(maybeCommand);
+        // we also need to wrap any children
+        for (final CommandNode<CommandSource> child : delegate.getChildren()) {
+          literalBuilder.then(wrap(child, registrant));
+        }
+        if (delegate.getRedirect() != null) {
+          literalBuilder.redirect(wrap(delegate.getRedirect(), registrant));
+        }
+        yield literalBuilder.build();
       }
-      if (delegate.getRedirect() != null) {
-        literalBuilder.redirect(wrap(delegate.getRedirect(), registrant));
+      case VelocityArgumentCommandNode<CommandSource, ?> vacn -> vacn.withCommand(maybeCommand)
+              .withRedirect(delegate.getRedirect() != null ? wrap(delegate.getRedirect(), registrant) : null);
+      case ArgumentCommandNode<CommandSource, ?> node -> {
+        var argBuilder = node.createBuilder().executes(maybeCommand);
+        // we also need to wrap any children
+        for (final CommandNode<CommandSource> child : delegate.getChildren()) {
+          argBuilder.then(wrap(child, registrant));
+        }
+        if (delegate.getRedirect() != null) {
+          argBuilder.redirect(wrap(delegate.getRedirect(), registrant));
+        }
+        yield argBuilder.build();
       }
-      return literalBuilder.build();
-    } else if (delegate instanceof VelocityArgumentCommandNode<CommandSource, ?> vacn) {
-      return vacn.withCommand(maybeCommand)
-          .withRedirect(delegate.getRedirect() != null ? wrap(delegate.getRedirect(), registrant) : null);
-    } else if (delegate instanceof ArgumentCommandNode) {
-      var argBuilder = delegate.createBuilder().executes(maybeCommand);
-      // we also need to wrap any children
-      for (final CommandNode<CommandSource> child : delegate.getChildren()) {
-        argBuilder.then(wrap(child, registrant));
-      }
-      if (delegate.getRedirect() != null) {
-        argBuilder.redirect(wrap(delegate.getRedirect(), registrant));
-      }
-      return argBuilder.build();
-    } else {
-      throw new IllegalArgumentException("Unsupported node type: " + delegate.getClass());
-    }
+      default -> throw new IllegalArgumentException("Unsupported node type: " + delegate.getClass());
+    };
   }
 
   // Normalization
@@ -133,7 +134,7 @@ public final class VelocityCommands {
     if (nodes.isEmpty()) {
       throw new IllegalArgumentException("Cannot read alias from empty node list");
     }
-    return nodes.get(0).getNode().getName();
+    return nodes.getFirst().getNode().getName();
   }
 
   public static final String ARGS_NODE_NAME = "arguments";

proxy/src/main/java/com/velocitypowered/proxy/command/brigadier/VelocityArgumentCommandNode.java

@@ -118,14 +118,12 @@ public class VelocityArgumentCommandNode<S, T> extends ArgumentCommandNode<S, St
     if (this == o) {
       return true;
     }
-    if (!(o instanceof VelocityArgumentCommandNode)) {
+    if (!(o instanceof VelocityArgumentCommandNode that)) {
       return false;
     }
-    if (!super.equals(o)) {
+    if (!super.equals(that)) {
       return false;
     }
-
-    final VelocityArgumentCommandNode<?, ?> that = (VelocityArgumentCommandNode<?, ?>) o;
     return this.type.equals(that.type);
   }
 

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/GlistCommand.java

@@ -38,6 +38,7 @@ import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.TranslatableComponent;
 import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.minimessage.translation.Argument;
 
 /**
  * Implements the Velocity default {@code /glist} command.
@@ -111,7 +112,7 @@ public class GlistCommand {
       if (registeredServer.isEmpty()) {
         source.sendMessage(
             CommandMessages.SERVER_DOES_NOT_EXIST
-                    .arguments(Component.text(serverName)));
+                    .arguments(Argument.string("server", serverName)));
         return -1;
       }
       sendServerPlayers(source, registeredServer.get(), false);
@@ -126,7 +127,8 @@ public class GlistCommand {
                   ? "velocity.command.glist-player-singular"
                   : "velocity.command.glist-player-plural"
             ).color(NamedTextColor.YELLOW)
-            .arguments(Component.text(Integer.toString(online), NamedTextColor.GREEN));
+            .arguments(Argument.component(
+                    "players", Component.text(Integer.toString(online), NamedTextColor.GREEN)));
     target.sendMessage(msg.build());
   }
 

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/SendCommand.java

@@ -35,6 +35,7 @@ import java.util.Objects;
 import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.minimessage.translation.Argument;
 
 /**
  * Implements the Velocity default {@code /send} command.
@@ -121,7 +122,7 @@ public class SendCommand {
 
     if (maybeServer.isEmpty()) {
       context.getSource().sendMessage(
-          CommandMessages.SERVER_DOES_NOT_EXIST.arguments(Component.text(serverName))
+          CommandMessages.SERVER_DOES_NOT_EXIST.arguments(Argument.string("server", serverName))
       );
       return 0;
     }
@@ -133,7 +134,7 @@ public class SendCommand {
         && !Objects.equals(player, "all")
         && !Objects.equals(player, "current")) {
       context.getSource().sendMessage(
-          CommandMessages.PLAYER_NOT_FOUND.arguments(Component.text(player))
+          CommandMessages.PLAYER_NOT_FOUND.arguments(Argument.string("player", player))
       );
       return 0;
     }

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/ServerCommand.java

@@ -37,6 +37,7 @@ import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.TranslatableComponent;
 import net.kyori.adventure.text.event.ClickEvent;
 import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.minimessage.translation.Argument;
 
 /**
  * Implements Velocity's {@code /server} command.
@@ -76,7 +77,7 @@ public final class ServerCommand {
               final Optional<RegisteredServer> toConnect = server.getServer(serverName);
               if (toConnect.isEmpty()) {
                 player.sendMessage(CommandMessages.SERVER_DOES_NOT_EXIST
-                        .arguments(Component.text(serverName)));
+                        .arguments(Argument.string("server", serverName)));
                 return -1;
               }
 
@@ -135,7 +136,7 @@ public final class ServerCommand {
     } else {
       playersTextComponent.key("velocity.command.server-tooltip-players-online");
     }
-    playersTextComponent.arguments(Component.text(connectedPlayers));
+    playersTextComponent.arguments(Argument.component("players", Component.text(connectedPlayers)));
     if (serverInfo.getName().equals(currentPlayerServer)) {
       serverTextComponent.color(NamedTextColor.GREEN)
           .hoverEvent(

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/VelocityCommand.java

@@ -62,6 +62,7 @@ import net.kyori.adventure.text.event.HoverEvent;
 import net.kyori.adventure.text.format.NamedTextColor;
 import net.kyori.adventure.text.format.TextColor;
 import net.kyori.adventure.text.format.TextDecoration;
+import net.kyori.adventure.text.minimessage.translation.Argument;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -165,9 +166,9 @@ public final class VelocityCommand {
           .build();
       final Component copyright = Component
           .translatable("velocity.command.version-copyright",
-              Component.text(version.getVendor()),
-                  Component.text(version.getName()),
-                  Component.text(LocalDate.now().getYear()));
+              Argument.string("vendor", version.getVendor()),
+                  Argument.string("name", version.getName()),
+                  Argument.component("year", Component.text(LocalDate.now().getYear())));
       source.sendMessage(velocity);
       source.sendMessage(copyright);
 
@@ -176,8 +177,7 @@ public final class VelocityCommand {
             .append(Component.text()
                 .content("PaperMC")
                 .color(NamedTextColor.GREEN)
-                .clickEvent(
-                    ClickEvent.openUrl("https://papermc.io/software/velocity"))
+                .clickEvent(ClickEvent.openUrl(VelocityServer.VELOCITY_URL))
                 .build())
             .append(Component.text(" - "))
             .append(Component.text()
@@ -221,7 +221,7 @@ public final class VelocityCommand {
       final TranslatableComponent output = Component.translatable()
           .key("velocity.command.plugins-list")
           .color(NamedTextColor.YELLOW)
-          .arguments(listBuilder.build())
+          .arguments(Argument.component("plugins", listBuilder.build()))
           .build();
       source.sendMessage(output);
       return Command.SINGLE_SUCCESS;
@@ -237,17 +237,17 @@ public final class VelocityCommand {
         hoverText.append(Component.newline());
         hoverText.append(Component.translatable(
             "velocity.command.plugin-tooltip-website",
-            Component.text(url)));
+            Argument.component("url", Component.text(url))));
       });
       if (!description.getAuthors().isEmpty()) {
         hoverText.append(Component.newline());
         if (description.getAuthors().size() == 1) {
           hoverText.append(Component.translatable("velocity.command.plugin-tooltip-author",
-              Component.text(description.getAuthors().get(0))));
+              Component.text(description.getAuthors().getFirst())));
         } else {
           hoverText.append(
               Component.translatable("velocity.command.plugin-tooltip-author",
-                  Component.text(String.join(", ", description.getAuthors()))
+                  Argument.string("authors", String.join(", ", description.getAuthors()))
               )
           );
         }

proxy/src/main/java/com/velocitypowered/proxy/command/registrar/InvocableCommandRegistrar.java

@@ -103,13 +103,17 @@ abstract class InvocableCommandRegistrar<T extends InvocableCommand<I>,
         .requiresWithContext((context, reader) -> requirement.test(context))
         .executes(callback)
         .suggests((context, builder) -> {
+          // Offset the suggestion to the last space seperated word
+          int lastSpace = builder.getRemaining().lastIndexOf(' ') + 1;
+          final var offsetBuilder = builder.createOffset(builder.getStart() + lastSpace);
+
           final I invocation = invocationFactory.create(context);
           return command.suggestAsync(invocation).thenApply(suggestions -> {
             for (String value : suggestions) {
               Preconditions.checkNotNull(value, "suggestion");
-              builder.suggest(value);
+              offsetBuilder.suggest(value);
             }
-            return builder.build();
+            return offsetBuilder.build();
           });
         })
         .build();

proxy/src/main/java/com/velocitypowered/proxy/config/VelocityConfiguration.java

@@ -29,6 +29,7 @@ import com.velocitypowered.api.util.Favicon;
 import com.velocitypowered.proxy.config.migration.ConfigurationMigration;
 import com.velocitypowered.proxy.config.migration.ForwardingMigration;
 import com.velocitypowered.proxy.config.migration.KeyAuthenticationMigration;
+import com.velocitypowered.proxy.config.migration.MiniMessageTranslationsMigration;
 import com.velocitypowered.proxy.config.migration.MotdMigration;
 import com.velocitypowered.proxy.config.migration.TransferIntegrationMigration;
 import com.velocitypowered.proxy.util.AddressUtil;
@@ -93,6 +94,8 @@ public class VelocityConfiguration implements ProxyConfig {
   private @Nullable Favicon favicon;
   @Expose
   private boolean forceKeyAuthentication = true; // Added in 1.19
+  @Expose
+  private PacketLimiterConfig packetLimiterConfig = PacketLimiterConfig.DEFAULT;
 
   private VelocityConfiguration(Servers servers, ForcedHosts forcedHosts, Advanced advanced,
       Query query, Metrics metrics) {
@@ -109,7 +112,7 @@ public class VelocityConfiguration implements ProxyConfig {
       boolean onlineModeKickExistingPlayers, PingPassthroughMode pingPassthrough,
       boolean samplePlayersInPing, boolean enablePlayerAddressLogging, Servers servers,
       ForcedHosts forcedHosts, Advanced advanced, Query query, Metrics metrics,
-      boolean forceKeyAuthentication) {
+      boolean forceKeyAuthentication, PacketLimiterConfig packetLimiterConfig) {
     this.bind = bind;
     this.motd = motd;
     this.showMaxPlayers = showMaxPlayers;
@@ -128,6 +131,7 @@ public class VelocityConfiguration implements ProxyConfig {
     this.query = query;
     this.metrics = metrics;
     this.forceKeyAuthentication = forceKeyAuthentication;
+    this.packetLimiterConfig = packetLimiterConfig;
   }
 
   /**
@@ -156,19 +160,16 @@ public class VelocityConfiguration implements ProxyConfig {
     }
 
     switch (playerInfoForwardingMode) {
-      case NONE:
-        logger.warn("Player info forwarding is disabled! All players will appear to be connecting "
+      case NONE -> logger.warn("Player info forwarding is disabled! All players will appear to be connecting "
             + "from the proxy and will have offline-mode UUIDs.");
-        break;
-      case MODERN:
-      case BUNGEEGUARD:
+      case MODERN, BUNGEEGUARD -> {
         if (forwardingSecret == null || forwardingSecret.length == 0) {
           logger.error("You don't have a forwarding secret set. This is required for security.");
           valid = false;
         }
-        break;
-      default:
-        break;
+      }
+      default -> {
+      }
     }
 
     if (servers.getServers().isEmpty()) {
@@ -449,6 +450,10 @@ public class VelocityConfiguration implements ProxyConfig {
     return advanced.isEnableReusePort();
   }
 
+  public PacketLimiterConfig getPacketLimiterConfig() {
+    return packetLimiterConfig;
+  }
+
   @Override
   public String toString() {
     return MoreObjects.toStringHelper(this)
@@ -466,6 +471,7 @@ public class VelocityConfiguration implements ProxyConfig {
         .add("favicon", favicon)
         .add("enablePlayerAddressLogging", enablePlayerAddressLogging)
         .add("forceKeyAuthentication", forceKeyAuthentication)
+        .add("packetLimiterConfig", packetLimiterConfig)
         .toString();
   }
 
@@ -504,6 +510,7 @@ public class VelocityConfiguration implements ProxyConfig {
           new ForwardingMigration(),
           new KeyAuthenticationMigration(),
           new MotdMigration(),
+          new MiniMessageTranslationsMigration(),
           new TransferIntegrationMigration()
       };
 
@@ -515,7 +522,7 @@ public class VelocityConfiguration implements ProxyConfig {
 
       String forwardingSecretString = System.getenv().getOrDefault(
               "VELOCITY_FORWARDING_SECRET", "");
-      if (forwardingSecretString.isEmpty()) {
+      if (forwardingSecretString.isBlank()) {
         final String forwardSecretFile = config.get("forwarding-secret-file");
         final Path secretPath = forwardSecretFile == null
                 ? defaultForwardingSecretPath
@@ -528,7 +535,11 @@ public class VelocityConfiguration implements ProxyConfig {
                     "The file " + forwardSecretFile + " is not a valid file or it is a directory.");
           }
         } else {
-          throw new RuntimeException("The forwarding-secret-file does not exist.");
+          Files.createFile(secretPath);
+          Files.writeString(secretPath, forwardingSecretString = generateRandomString(12),
+              StandardCharsets.UTF_8);
+          logger.info("The forwarding-secret-file does not exist. A new file has been created at {}",
+              forwardSecretFile);
         }
       }
       final byte[] forwardingSecret = forwardingSecretString.getBytes(StandardCharsets.UTF_8);
@@ -557,6 +568,7 @@ public class VelocityConfiguration implements ProxyConfig {
       final boolean kickExisting = config.getOrElse("kick-existing-players", false);
       final boolean enablePlayerAddressLogging = config.getOrElse(
               "enable-player-address-logging", true);
+      final PacketLimiterConfig packetLimiterConfig = PacketLimiterConfig.fromConfig(config.get("packet-limiter"));
 
       // Throw an exception if the forwarding-secret file is empty and the proxy is using a
       // forwarding mode that requires it.
@@ -584,7 +596,8 @@ public class VelocityConfiguration implements ProxyConfig {
               new Advanced(advancedConfig),
               new Query(queryConfig),
               new Metrics(metricsConfig),
-              forceKeyAuthentication
+              forceKeyAuthentication,
+              packetLimiterConfig
       );
     }
   }
@@ -987,4 +1000,33 @@ public class VelocityConfiguration implements ProxyConfig {
       return enabled;
     }
   }
+
+  /**
+   * Configuration for packet limiting.
+   *
+   * @param interval the interval in seconds to measure packets over
+   * @param pps      the maximum number of packets per second allowed
+   * @param bytes    the maximum number of bytes per second allowed
+   */
+  public record PacketLimiterConfig(int interval, int pps, int bytes) {
+    public static PacketLimiterConfig DEFAULT = new PacketLimiterConfig(7, 500, -1);
+
+    /**
+     * returns a PacketLimiterConfig from a config section, or the default if the section is null.
+     *
+     * @param config the configuration object to parse
+     * @return the packet limiter config, or the default if {@code config} is null
+     */
+    public static PacketLimiterConfig fromConfig(CommentedConfig config) {
+      if (config != null) {
+        return new PacketLimiterConfig(
+            config.getIntOrElse("interval", DEFAULT.interval()),
+            config.getIntOrElse("packets-per-second", DEFAULT.pps()),
+            config.getIntOrElse("bytes-per-second", DEFAULT.bytes())
+        );
+      } else {
+        return DEFAULT;
+      }
+    }
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/config/migration/ConfigurationMigration.java

@@ -28,6 +28,7 @@ public sealed interface ConfigurationMigration
         permits ForwardingMigration,
                 KeyAuthenticationMigration,
                 MotdMigration,
+                MiniMessageTranslationsMigration,
                 TransferIntegrationMigration {
   boolean shouldMigrate(CommentedFileConfig config);
 

proxy/src/main/java/com/velocitypowered/proxy/config/migration/MiniMessageTranslationsMigration.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2024 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.config.migration;
+
+import com.electronwill.nightconfig.core.file.CommentedFileConfig;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.DirectoryStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.regex.Pattern;
+import net.kyori.adventure.text.minimessage.MiniMessage;
+import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
+import org.apache.logging.log4j.Logger;
+
+/**
+ * Migration from old to modern language argument format with MiniMessage.
+ * Also migrates possible use of legacy colors to MiniMessage format.
+ */
+public final class MiniMessageTranslationsMigration implements ConfigurationMigration {
+  @Override
+  public boolean shouldMigrate(final CommentedFileConfig config) {
+    // Checking whether translations should be migrated would be just as costly as attempting to migrate them directly.
+    return true;
+  }
+
+  @Override
+  public void migrate(final CommentedFileConfig config, final Logger logger) throws IOException {
+    final Path langFolder = Path.of("lang");
+    if (Files.notExists(langFolder)) {
+      return;
+    }
+    final Pattern oldPlaceholderPattern = Pattern.compile("\\{(\\d+)}");
+    try (final DirectoryStream<Path> stream
+                 = Files.newDirectoryStream(langFolder, Files::isRegularFile)) {
+      for (final Path path : stream) {
+        String content = Files.readString(path, StandardCharsets.UTF_8);
+        if (content.indexOf('{') == -1) {
+          continue;
+        }
+        // Migrate old arguments
+        content = oldPlaceholderPattern.matcher(content).replaceAll("<arg:$1>");
+        // Some setups use legacy color codes, this format is migrated to MiniMessage
+        content = MiniMessage.miniMessage().serialize(
+                LegacyComponentSerializer.legacySection().deserialize(content));
+        Files.writeString(path, content, StandardCharsets.UTF_8);
+      }
+    }
+  }
+}

proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java

@@ -33,6 +33,7 @@ import com.velocitypowered.natives.encryption.VelocityCipher;
 import com.velocitypowered.natives.encryption.VelocityCipherFactory;
 import com.velocitypowered.natives.util.Natives;
 import com.velocitypowered.proxy.VelocityServer;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.connection.client.HandshakeSessionHandler;
 import com.velocitypowered.proxy.connection.client.InitialLoginSessionHandler;
 import com.velocitypowered.proxy.connection.client.StatusSessionHandler;
@@ -66,7 +67,7 @@ import io.netty.util.ReferenceCountUtil;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.security.GeneralSecurityException;
-import java.util.HashMap;
+import java.util.EnumMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;
@@ -108,7 +109,7 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
     this.server = server;
     this.state = StateRegistry.HANDSHAKE;
 
-    this.sessionHandlers = new HashMap<>();
+    this.sessionHandlers = new EnumMap<>(StateRegistry.class);
   }
 
   @Override
@@ -153,13 +154,13 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
 
       if (msg instanceof MinecraftPacket pkt) {
         if (!pkt.handle(activeSessionHandler)) {
-          activeSessionHandler.handleGeneric((MinecraftPacket) msg);
+          activeSessionHandler.handleGeneric(pkt);
         }
       } else if (msg instanceof HAProxyMessage proxyMessage) {
         this.remoteAddress = new InetSocketAddress(proxyMessage.sourceAddress(),
             proxyMessage.sourcePort());
-      } else if (msg instanceof ByteBuf) {
-        activeSessionHandler.handleUnknown((ByteBuf) msg);
+      } else if (msg instanceof ByteBuf buf) {
+        activeSessionHandler.handleUnknown(buf);
       }
     } finally {
       ReferenceCountUtil.release(msg);
@@ -368,6 +369,7 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
   public void setState(StateRegistry state) {
     ensureInEventLoop();
 
+    final StateRegistry previousState = this.state;
     this.state = state;
     final MinecraftVarintFrameDecoder frameDecoder = this.channel.pipeline()
         .get(MinecraftVarintFrameDecoder.class);
@@ -388,7 +390,13 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
 
     if (state == StateRegistry.CONFIG) {
       // Activate the play packet queue
-      addPlayPacketQueueHandler();
+      if (previousState == StateRegistry.PLAY
+          && this.pendingConfigurationSwitch
+          && this.association instanceof ConnectedPlayer) {
+        addPlayPacketQueueOutboundHandler();
+      } else {
+        addPlayPacketQueueHandler();
+      }
     } else {
       // Remove the queue
       if (this.channel.pipeline().get(Connections.PLAY_PACKET_QUEUE_OUTBOUND) != null) {
@@ -404,13 +412,23 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
    * Adds the play packet queue handler.
    */
   public void addPlayPacketQueueHandler() {
-    if (this.channel.pipeline().get(Connections.PLAY_PACKET_QUEUE_OUTBOUND) == null) {
-      this.channel.pipeline().addAfter(Connections.MINECRAFT_ENCODER, Connections.PLAY_PACKET_QUEUE_OUTBOUND,
-           new PlayPacketQueueOutboundHandler(this.protocolVersion, channel.pipeline().get(MinecraftEncoder.class).getDirection()));
-    }
+    addPlayPacketQueueOutboundHandler();
+
     if (this.channel.pipeline().get(Connections.PLAY_PACKET_QUEUE_INBOUND) == null) {
       this.channel.pipeline().addAfter(Connections.MINECRAFT_DECODER, Connections.PLAY_PACKET_QUEUE_INBOUND,
-           new PlayPacketQueueInboundHandler(this.protocolVersion, channel.pipeline().get(MinecraftDecoder.class).getDirection()));
+           new PlayPacketQueueInboundHandler(this.protocolVersion,
+               channel.pipeline().get(MinecraftDecoder.class).getDirection()));
+    }
+  }
+
+  /**
+   * Adds only the outbound play packet queue handler.
+   */
+  public void addPlayPacketQueueOutboundHandler() {
+    if (this.channel.pipeline().get(Connections.PLAY_PACKET_QUEUE_OUTBOUND) == null) {
+      this.channel.pipeline().addAfter(Connections.MINECRAFT_ENCODER, Connections.PLAY_PACKET_QUEUE_OUTBOUND,
+           new PlayPacketQueueOutboundHandler(this.protocolVersion,
+               channel.pipeline().get(MinecraftEncoder.class).getDirection()));
     }
   }
 
@@ -544,9 +562,10 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
       } else {
         int level = server.getConfiguration().getCompressionLevel();
         VelocityCompressor compressor = Natives.compress.get().create(level);
+        final MinecraftDecoder minecraftDecoder = (MinecraftDecoder) channel.pipeline().get(MINECRAFT_DECODER);
 
         encoder = new MinecraftCompressorAndLengthEncoder(threshold, compressor);
-        decoder = new MinecraftCompressDecoder(threshold, compressor);
+        decoder = new MinecraftCompressDecoder(threshold, compressor, minecraftDecoder.getDirection());
 
         channel.pipeline().remove(FRAME_ENCODER);
         channel.pipeline().addBefore(MINECRAFT_DECODER, COMPRESSION_DECODER, decoder);

proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftSessionHandler.java

@@ -23,7 +23,11 @@ import com.velocitypowered.proxy.protocol.packet.BossBarPacket;
 import com.velocitypowered.proxy.protocol.packet.BundleDelimiterPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientSettingsPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundCookieRequestPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundSoundEntityPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundStopSoundPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundStoreCookiePacket;
+import com.velocitypowered.proxy.protocol.packet.DialogClearPacket;
+import com.velocitypowered.proxy.protocol.packet.DialogShowPacket;
 import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
 import com.velocitypowered.proxy.protocol.packet.EncryptionRequestPacket;
 import com.velocitypowered.proxy.protocol.packet.EncryptionResponsePacket;
@@ -48,6 +52,7 @@ import com.velocitypowered.proxy.protocol.packet.ServerDataPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerLoginPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccessPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerboundCookieResponsePacket;
+import com.velocitypowered.proxy.protocol.packet.ServerboundCustomClickActionPacket;
 import com.velocitypowered.proxy.protocol.packet.SetCompressionPacket;
 import com.velocitypowered.proxy.protocol.packet.StatusPingPacket;
 import com.velocitypowered.proxy.protocol.packet.StatusRequestPacket;
@@ -67,6 +72,8 @@ import com.velocitypowered.proxy.protocol.packet.chat.session.SessionPlayerComma
 import com.velocitypowered.proxy.protocol.packet.config.ActiveFeaturesPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundCustomReportDetailsPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundServerLinksPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductAcceptPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductPacket;
 import com.velocitypowered.proxy.protocol.packet.config.FinishedUpdatePacket;
 import com.velocitypowered.proxy.protocol.packet.config.KnownPacksPacket;
 import com.velocitypowered.proxy.protocol.packet.config.RegistrySyncPacket;
@@ -364,4 +371,32 @@ public interface MinecraftSessionHandler {
   default boolean handle(ClientboundServerLinksPacket packet) {
     return false;
   }
+
+  default boolean handle(DialogClearPacket packet) {
+    return false;
+  }
+
+  default boolean handle(DialogShowPacket packet) {
+    return false;
+  }
+
+  default boolean handle(ServerboundCustomClickActionPacket packet) {
+    return false;
+  }
+
+  default boolean handle(CodeOfConductPacket packet) {
+    return false;
+  }
+
+  default boolean handle(CodeOfConductAcceptPacket packet) {
+    return false;
+  }
+
+  default boolean handle(ClientboundSoundEntityPacket packet) {
+    return false;
+  }
+
+  default boolean handle(ClientboundStopSoundPacket packet) {
+    return false;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BackendPlaySessionHandler.java

@@ -34,6 +34,8 @@ import com.velocitypowered.api.event.player.ServerResourcePackSendEvent;
 import com.velocitypowered.api.event.proxy.ProxyPingEvent;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.LegacyChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.MinecraftChannelIdentifier;
 import com.velocitypowered.api.proxy.player.ResourcePackInfo;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.command.CommandGraphInjector;
@@ -68,6 +70,7 @@ import com.velocitypowered.proxy.protocol.packet.TransferPacket;
 import com.velocitypowered.proxy.protocol.packet.UpsertPlayerInfoPacket;
 import com.velocitypowered.proxy.protocol.packet.chat.ComponentHolder;
 import com.velocitypowered.proxy.protocol.packet.config.StartUpdatePacket;
+import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
 import com.velocitypowered.proxy.protocol.util.PluginMessageUtil;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
@@ -91,6 +94,7 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
       Boolean.getBoolean("velocity.log-server-backpressure");
   private static final int MAXIMUM_PACKETS_TO_FLUSH =
       Integer.getInteger("velocity.max-packets-per-flush", 8192);
+  private static final int LARGE_PACKET_THRESHOLD = 1024 * 128;
 
   private final VelocityServer server;
   private final VelocityServerConnection serverConn;
@@ -177,10 +181,12 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
 
   @Override
   public boolean handle(BossBarPacket packet) {
-    if (packet.getAction() == BossBarPacket.ADD) {
-      playerSessionHandler.getServerBossBars().add(packet.getUuid());
-    } else if (packet.getAction() == BossBarPacket.REMOVE) {
-      playerSessionHandler.getServerBossBars().remove(packet.getUuid());
+    if (serverConn.getPlayer().getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_20_2)) {
+      if (packet.getAction() == BossBarPacket.ADD) {
+        playerSessionHandler.getServerBossBars().add(packet.getUuid());
+      } else if (packet.getAction() == BossBarPacket.REMOVE) {
+        playerSessionHandler.getServerBossBars().remove(packet.getUuid());
+      }
     }
     return false; // forward
   }
@@ -290,31 +296,14 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
       return true;
     }
 
-    // Register and unregister packets are simply forwarded to the server as-is.
-    if (PluginMessageUtil.isRegister(packet) || PluginMessageUtil.isUnregister(packet)) {
-      return false;
-    }
-
-    if (PluginMessageUtil.isMcBrand(packet)) {
-      PluginMessagePacket rewritten = PluginMessageUtil
-              .rewriteMinecraftBrand(packet,
-                      server.getVersion(), playerConnection.getProtocolVersion());
-      playerConnection.write(rewritten);
-      return true;
-    }
-
     if (serverConn.getPhase().handle(serverConn, serverConn.getPlayer(), packet)) {
       // Handled.
       return true;
     }
 
-    ChannelIdentifier id = server.getChannelRegistrar().getFromId(packet.getChannel());
-    if (id == null) {
-      return false;
-    }
-
     byte[] copy = ByteBufUtil.getBytes(packet.content());
-    PluginMessageEvent event = new PluginMessageEvent(serverConn, serverConn.getPlayer(), id, copy);
+    String channel = packet.getChannel();
+    PluginMessageEvent event = new PluginMessageEvent(serverConn, serverConn.getPlayer(), channel.indexOf(':') == -1 ? new LegacyChannelIdentifier(channel) : MinecraftChannelIdentifier.from(channel), copy);
     server.getEventManager().fire(event).thenAcceptAsync(pme -> {
       if (pme.getResult().isAllowed() && !playerConnection.isClosed()) {
         PluginMessagePacket copied = new PluginMessagePacket(
@@ -359,7 +348,12 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
       // Inject commands from the proxy.
       final CommandGraphInjector<CommandSource> injector = server.getCommandManager().getInjector();
       injector.inject(rootNode, serverConn.getPlayer());
-      rootNode.removeChildByName("velocity:callback");
+
+      // In 1.21.6 a confirmation prompt was added when executing a command via `run_command` click
+      // action if the command is unknown. To prevent this prompt we have to send the command.
+      if (this.playerConnection.getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_21_6)) {
+        rootNode.removeChildByName("velocity:callback");
+      }
     }
 
     server.getEventManager().fire(
@@ -445,11 +439,12 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
 
   @Override
   public void handleGeneric(MinecraftPacket packet) {
-    if (packet instanceof PluginMessagePacket) {
-      ((PluginMessagePacket) packet).retain();
+    if (packet instanceof PluginMessagePacket pluginMessage) {
+      pluginMessage.retain();
     }
+    boolean huge = packet instanceof DeferredByteBufHolder def && def.content().readableBytes() > LARGE_PACKET_THRESHOLD;
     playerConnection.delayedWrite(packet);
-    if (++packetsFlushed >= MAXIMUM_PACKETS_TO_FLUSH) {
+    if (huge || ++packetsFlushed >= MAXIMUM_PACKETS_TO_FLUSH) {
       playerConnection.flush();
       packetsFlushed = 0;
     }
@@ -457,8 +452,9 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
 
   @Override
   public void handleUnknown(ByteBuf buf) {
+    boolean huge = buf.readableBytes() > LARGE_PACKET_THRESHOLD;
     playerConnection.delayedWrite(buf.retain());
-    if (++packetsFlushed >= MAXIMUM_PACKETS_TO_FLUSH) {
+    if (huge || ++packetsFlushed >= MAXIMUM_PACKETS_TO_FLUSH) {
       playerConnection.flush();
       packetsFlushed = 0;
     }
@@ -511,4 +507,4 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
 
     playerConnection.setAutoReading(writable);
   }
-}
+}

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BungeeCordMessageResponder.java

@@ -344,66 +344,30 @@ public class BungeeCordMessageResponder {
       return false;
     }
 
-    ByteBufDataInput in = new ByteBufDataInput(message.content());
-    String subChannel = in.readUTF();
+    final ByteBufDataInput in = new ByteBufDataInput(message.content());
+    final String subChannel = in.readUTF();
     switch (subChannel) {
-      case "GetPlayerServer":
-        this.processGetPlayerServer(in);
-        break;
-      case "ForwardToPlayer":
-        this.processForwardToPlayer(in);
-        break;
-      case "Forward":
-        this.processForwardToServer(in);
-        break;
-      case "Connect":
-        this.processConnect(in);
-        break;
-      case "ConnectOther":
-        this.processConnectOther(in);
-        break;
-      case "IP":
-        this.processIp(in);
-        break;
-      case "PlayerCount":
-        this.processPlayerCount(in);
-        break;
-      case "PlayerList":
-        this.processPlayerList(in);
-        break;
-      case "GetServers":
-        this.processGetServers();
-        break;
-      case "Message":
-        this.processMessage(in);
-        break;
-      case "MessageRaw":
-        this.processMessageRaw(in);
-        break;
-      case "GetServer":
-        this.processGetServer();
-        break;
-      case "UUID":
-        this.processUuid();
-        break;
-      case "UUIDOther":
-        this.processUuidOther(in);
-        break;
-      case "IPOther":
-        this.processIpOther(in);
-        break;
-      case "ServerIP":
-        this.processServerIp(in);
-        break;
-      case "KickPlayer":
-        this.processKick(in);
-        break;
-      case "KickPlayerRaw":
-        this.processKickRaw(in);
-        break;
-      default:
-        // Do nothing, unknown command
-        break;
+      case "GetPlayerServer" -> this.processGetPlayerServer(in);
+      case "ForwardToPlayer" -> this.processForwardToPlayer(in);
+      case "Forward" -> this.processForwardToServer(in);
+      case "Connect" -> this.processConnect(in);
+      case "ConnectOther" -> this.processConnectOther(in);
+      case "IP" -> this.processIp(in);
+      case "PlayerCount" -> this.processPlayerCount(in);
+      case "PlayerList" -> this.processPlayerList(in);
+      case "GetServers" -> this.processGetServers();
+      case "Message" -> this.processMessage(in);
+      case "MessageRaw" -> this.processMessageRaw(in);
+      case "GetServer" -> this.processGetServer();
+      case "UUID" -> this.processUuid();
+      case "UUIDOther" -> this.processUuidOther(in);
+      case "IPOther" -> this.processIpOther(in);
+      case "ServerIP" -> this.processServerIp(in);
+      case "KickPlayer" -> this.processKick(in);
+      case "KickPlayerRaw" -> this.processKickRaw(in);
+      default -> {
+          // Do nothing, unknown command
+      }
     }
 
     return true;

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/ConfigSessionHandler.java

@@ -52,6 +52,7 @@ import com.velocitypowered.proxy.protocol.packet.ResourcePackResponsePacket;
 import com.velocitypowered.proxy.protocol.packet.TransferPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundCustomReportDetailsPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundServerLinksPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductPacket;
 import com.velocitypowered.proxy.protocol.packet.config.FinishedUpdatePacket;
 import com.velocitypowered.proxy.protocol.packet.config.RegistrySyncPacket;
 import com.velocitypowered.proxy.protocol.packet.config.StartUpdatePacket;
@@ -59,7 +60,7 @@ import com.velocitypowered.proxy.protocol.packet.config.TagsUpdatePacket;
 import com.velocitypowered.proxy.protocol.util.PluginMessageUtil;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.Unpooled;
-import java.io.IOException;
+import io.netty.channel.Channel;
 import java.net.InetSocketAddress;
 import java.util.concurrent.CompletableFuture;
 import net.kyori.adventure.key.Key;
@@ -71,6 +72,9 @@ import org.apache.logging.log4j.Logger;
  * 1.20.2+ switching. Yes, some of this is exceptionally stupid.
  */
 public class ConfigSessionHandler implements MinecraftSessionHandler {
+  private static final boolean BACKPRESSURE_LOG =
+      Boolean.getBoolean("velocity.log-server-backpressure");
+
   private static final Logger logger = LogManager.getLogger(ConfigSessionHandler.class);
   private final VelocityServer server;
   private final VelocityServerConnection serverConn;
@@ -256,7 +260,13 @@ public class ConfigSessionHandler implements MinecraftSessionHandler {
   @Override
   public boolean handle(DisconnectPacket packet) {
     serverConn.disconnect();
-    resultFuture.complete(ConnectionRequestResults.forDisconnect(packet, serverConn.getServer()));
+    // If the player receives a DisconnectPacket without a connection to a server in progress,
+    // it means that the backend server has kicked the player during reconfiguration
+    if (serverConn.getPlayer().getConnectionInFlight() != null) {
+      resultFuture.complete(ConnectionRequestResults.forDisconnect(packet, serverConn.getServer()));
+    } else {
+      serverConn.getPlayer().handleConnectionException(serverConn.getServer(), packet, true);
+    }
     return true;
   }
 
@@ -358,10 +368,16 @@ public class ConfigSessionHandler implements MinecraftSessionHandler {
     return true;
   }
 
+  @Override
+  public boolean handle(CodeOfConductPacket packet) {
+    this.serverConn.getPlayer().getConnection().write(packet.retain());
+    return true;
+  }
+
   @Override
   public void disconnected() {
-    resultFuture.completeExceptionally(
-        new IOException("Unexpectedly disconnected from remote server"));
+    resultFuture.complete(ConnectionRequestResults.forDisconnect(
+        ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR, serverConn.getServer()));
   }
 
   @Override
@@ -369,6 +385,22 @@ public class ConfigSessionHandler implements MinecraftSessionHandler {
     serverConn.getPlayer().getConnection().write(packet);
   }
 
+  @Override
+  public void writabilityChanged() {
+    Channel serverChan = serverConn.ensureConnected().getChannel();
+    boolean writable = serverChan.isWritable();
+
+    if (BACKPRESSURE_LOG) {
+      if (writable) {
+        logger.info("{} is writable, will auto-read player connection data", this.serverConn);
+      } else {
+        logger.info("{} is not writable, not auto-reading player connection data", this.serverConn);
+      }
+    }
+
+    serverConn.getPlayer().getConnection().setAutoReading(writable);
+  }
+
   private void switchFailure(Throwable cause) {
     logger.error("Unable to switch to new server {} for {}", serverConn.getServerInfo().getName(),
         serverConn.getPlayer().getUsername(), cause);
@@ -382,4 +414,4 @@ public class ConfigSessionHandler implements MinecraftSessionHandler {
   public enum State {
     START, NEGOTIATING, PLUGIN_MESSAGE_INTERRUPT, RESOURCE_PACK_INTERRUPT, COMPLETE
   }
-}
+}

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/LoginSessionHandler.java

@@ -165,7 +165,7 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
       }
       if (player.getConnection().getActiveSessionHandler() instanceof ClientPlaySessionHandler clientPlaySessionHandler) {
         smc.setAutoReading(false);
-        clientPlaySessionHandler.doSwitch().thenAcceptAsync((unused) -> smc.setAutoReading(true), smc.eventLoop());
+        clientPlaySessionHandler.doSwitch().thenRunAsync(() -> smc.setAutoReading(true), smc.eventLoop());
       } else {
         // Initial login - the player is already in configuration state.
         server.getEventManager().fireAndForget(new PlayerEnteredConfigurationEvent(player, serverConn));

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/TransitionSessionHandler.java

@@ -38,7 +38,6 @@ import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
 import com.velocitypowered.proxy.protocol.packet.JoinGamePacket;
 import com.velocitypowered.proxy.protocol.packet.KeepAlivePacket;
 import com.velocitypowered.proxy.protocol.packet.PluginMessagePacket;
-import java.io.IOException;
 import java.util.concurrent.CompletableFuture;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -122,9 +121,8 @@ public class TransitionSessionHandler implements MinecraftSessionHandler {
           // Change the client to use the ClientPlaySessionHandler if required.
           ClientPlaySessionHandler playHandler;
           if (player.getConnection()
-              .getActiveSessionHandler() instanceof ClientPlaySessionHandler) {
-            playHandler =
-                (ClientPlaySessionHandler) player.getConnection().getActiveSessionHandler();
+              .getActiveSessionHandler() instanceof ClientPlaySessionHandler sessionHandler) {
+            playHandler = sessionHandler;
           } else {
             playHandler = new ClientPlaySessionHandler(server, player);
             player.getConnection().setActiveSessionHandler(StateRegistry.PLAY, playHandler);
@@ -214,7 +212,7 @@ public class TransitionSessionHandler implements MinecraftSessionHandler {
 
   @Override
   public void disconnected() {
-    resultFuture
-        .completeExceptionally(new IOException("Unexpectedly disconnected from remote server"));
+    resultFuture.complete(ConnectionRequestResults.forDisconnect(
+        ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR, serverConn.getServer()));
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/VelocityServerConnection.java

@@ -53,6 +53,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.NotNull;
 
@@ -70,6 +71,7 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
   private boolean gracefulDisconnect = false;
   private BackendConnectionPhase connectionPhase = BackendConnectionPhases.UNKNOWN;
   private final Map<Long, Long> pendingPings = new HashMap<>();
+  private @MonotonicNonNull Integer entityId;
 
   /**
    * Initializes a new server connection.
@@ -178,9 +180,8 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
       handshake.setServerAddress(createBungeeGuardForwardingAddress(secret));
     } else if (proxyPlayer.getConnection().getType() == ConnectionTypes.LEGACY_FORGE) {
       handshake.setServerAddress(playerVhost + HANDSHAKE_HOSTNAME_TOKEN);
-    } else if (proxyPlayer.getConnection().getType() instanceof ModernForgeConnectionType) {
-      handshake.setServerAddress(playerVhost + ((ModernForgeConnectionType) proxyPlayer
-              .getConnection().getType()).getModernToken());
+    } else if (proxyPlayer.getConnection().getType() instanceof ModernForgeConnectionType forgeConnection) {
+      handshake.setServerAddress(playerVhost + forgeConnection.getModernToken());
     } else {
       handshake.setServerAddress(playerVhost);
     }
@@ -324,6 +325,14 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
     return pendingPings;
   }
 
+  public Integer getEntityId() {
+    return entityId;
+  }
+
+  public void setEntityId(Integer entityId) {
+    this.entityId = entityId;
+  }
+
   /**
    * Ensures that this server connection remains "active": the connection is established and not
    * closed, the player is still connected to the server, and the player still remains online.

proxy/src/main/java/com/velocitypowered/proxy/connection/client/AuthSessionHandler.java

@@ -69,14 +69,16 @@ public class AuthSessionHandler implements MinecraftSessionHandler {
   private @MonotonicNonNull ConnectedPlayer connectedPlayer;
   private final boolean onlineMode;
   private State loginState = State.START; // 1.20.2+
+  private final String serverIdHash;
 
   AuthSessionHandler(VelocityServer server, LoginInboundConnection inbound,
-      GameProfile profile, boolean onlineMode) {
+      GameProfile profile, boolean onlineMode, String serverIdHash) {
     this.server = Preconditions.checkNotNull(server, "server");
     this.inbound = Preconditions.checkNotNull(inbound, "inbound");
     this.profile = Preconditions.checkNotNull(profile, "profile");
     this.onlineMode = onlineMode;
     this.mcConnection = inbound.delegatedConnection();
+    this.serverIdHash = serverIdHash;
   }
 
   @Override
@@ -213,7 +215,7 @@ public class AuthSessionHandler implements MinecraftSessionHandler {
   private void completeLoginProtocolPhaseAndInitialize(ConnectedPlayer player) {
     mcConnection.setAssociation(player);
 
-    server.getEventManager().fire(new LoginEvent(player)).thenAcceptAsync(event -> {
+    server.getEventManager().fire(new LoginEvent(player, serverIdHash)).thenAcceptAsync(event -> {
       if (mcConnection.isClosed()) {
         // The player was disconnected
         server.getEventManager().fireAndForget(new DisconnectEvent(player,

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientConfigSessionHandler.java

@@ -33,6 +33,7 @@ import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackResp
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
+import com.velocitypowered.proxy.protocol.netty.MinecraftDecoder;
 import com.velocitypowered.proxy.protocol.netty.MinecraftEncoder;
 import com.velocitypowered.proxy.protocol.packet.ClientSettingsPacket;
 import com.velocitypowered.proxy.protocol.packet.KeepAlivePacket;
@@ -40,6 +41,8 @@ import com.velocitypowered.proxy.protocol.packet.PingIdentifyPacket;
 import com.velocitypowered.proxy.protocol.packet.PluginMessagePacket;
 import com.velocitypowered.proxy.protocol.packet.ResourcePackResponsePacket;
 import com.velocitypowered.proxy.protocol.packet.ServerboundCookieResponsePacket;
+import com.velocitypowered.proxy.protocol.packet.ServerboundCustomClickActionPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductAcceptPacket;
 import com.velocitypowered.proxy.protocol.packet.config.FinishedUpdatePacket;
 import com.velocitypowered.proxy.protocol.packet.config.KnownPacksPacket;
 import com.velocitypowered.proxy.protocol.util.PluginMessageUtil;
@@ -58,6 +61,8 @@ import org.apache.logging.log4j.Logger;
  * Handles the client config stage.
  */
 public class ClientConfigSessionHandler implements MinecraftSessionHandler {
+  private static final boolean BACKPRESSURE_LOG =
+      Boolean.getBoolean("velocity.log-server-backpressure");
 
   private static final Logger logger = LogManager.getLogger(ClientConfigSessionHandler.class);
   private final VelocityServer server;
@@ -205,6 +210,26 @@ public class ClientConfigSessionHandler implements MinecraftSessionHandler {
     return true;
   }
 
+  @Override
+  public boolean handle(ServerboundCustomClickActionPacket packet) {
+    if (player.getConnectionInFlight() != null) {
+      player.getConnectionInFlight().ensureConnected().write(packet.retain());
+      return true;
+    }
+
+    return false;
+  }
+
+  @Override
+  public boolean handle(CodeOfConductAcceptPacket packet) {
+    if (this.player.getConnectionInFlight() != null) {
+      this.player.getConnectionInFlight().ensureConnected().write(packet);
+      return true;
+    }
+
+    return false;
+  }
+
   @Override
   public void handleGeneric(MinecraftPacket packet) {
     VelocityServerConnection serverConnection = player.getConnectedServer();
@@ -244,6 +269,36 @@ public class ClientConfigSessionHandler implements MinecraftSessionHandler {
   @Override
   public void exception(Throwable throwable) {
     player.disconnect(Component.translatable("velocity.error.player-connection-error", NamedTextColor.RED));
+    if (MinecraftDecoder.DEBUG) {
+      logger.info("Exception while handling packet for {}", player, throwable);
+    }
+  }
+
+  @Override
+  public void writabilityChanged() {
+    final boolean writable = player.getConnection().getChannel().isWritable();
+
+    if (BACKPRESSURE_LOG) {
+      if (writable) {
+        logger.info("{} is writable, will auto-read backend connection data", player);
+      } else {
+        logger.info("{} is not writable, not auto-reading backend connection data", player);
+      }
+    }
+
+    if (!writable) {
+      // Flush pending packets to free up memory. Schedule on a future event loop invocation
+      // to avoid disabling auto-read while the flush resolves backpressure.
+      player.getConnection().eventLoop().execute(() -> player.getConnection().flush());
+    }
+
+    final VelocityServerConnection serverConn = player.getConnectionInFlightOrConnectedServer();
+    if (serverConn != null) {
+      final MinecraftConnection smc = serverConn.getConnection();
+      if (smc != null) {
+        smc.setAutoReading(writable);
+      }
+    }
   }
 
   /**

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java

@@ -21,15 +21,17 @@ import static com.velocitypowered.proxy.protocol.util.PluginMessageUtil.construc
 
 import com.google.common.collect.ImmutableList;
 import com.mojang.brigadier.suggestion.Suggestion;
-import com.velocitypowered.api.command.VelocityBrigadierMessage;
 import com.velocitypowered.api.event.connection.PluginMessageEvent;
 import com.velocitypowered.api.event.player.CookieReceiveEvent;
 import com.velocitypowered.api.event.player.PlayerChannelRegisterEvent;
+import com.velocitypowered.api.event.player.PlayerChannelUnregisterEvent;
 import com.velocitypowered.api.event.player.PlayerClientBrandEvent;
 import com.velocitypowered.api.event.player.TabCompleteEvent;
 import com.velocitypowered.api.event.player.configuration.PlayerEnteredConfigurationEvent;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.api.proxy.messages.ChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.LegacyChannelIdentifier;
+import com.velocitypowered.api.proxy.messages.MinecraftChannelIdentifier;
 import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.ConnectionTypes;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
@@ -41,6 +43,7 @@ import com.velocitypowered.proxy.connection.forge.legacy.LegacyForgeConstants;
 import com.velocitypowered.proxy.connection.player.resourcepack.ResourcePackResponseBundle;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.StateRegistry;
+import com.velocitypowered.proxy.protocol.netty.MinecraftDecoder;
 import com.velocitypowered.proxy.protocol.packet.BossBarPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientSettingsPacket;
 import com.velocitypowered.proxy.protocol.packet.JoinGamePacket;
@@ -87,6 +90,7 @@ import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ConcurrentLinkedQueue;
 import net.kyori.adventure.key.Key;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.ComponentLike;
 import net.kyori.adventure.text.format.NamedTextColor;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -97,6 +101,8 @@ import org.checkerframework.checker.nullness.qual.Nullable;
  * center that joins backend servers with players.
  */
 public class ClientPlaySessionHandler implements MinecraftSessionHandler {
+  private static final boolean BACKPRESSURE_LOG =
+      Boolean.getBoolean("velocity.log-server-backpressure");
 
   private static final Logger logger = LogManager.getLogger(ClientPlaySessionHandler.class);
 
@@ -318,8 +324,12 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
                 new PlayerChannelRegisterEvent(player, ImmutableList.copyOf(channels)));
         backendConn.write(packet.retain());
       } else if (PluginMessageUtil.isUnregister(packet)) {
-        player.getClientsideChannels()
-            .removeAll(PluginMessageUtil.getChannels(0, packet, this.player.getProtocolVersion()));
+        List<ChannelIdentifier> channels =
+            PluginMessageUtil.getChannels(0, packet, this.player.getProtocolVersion());
+        player.getClientsideChannels().removeAll(channels);
+        server.getEventManager()
+            .fireAndForget(
+                new PlayerChannelUnregisterEvent(player, ImmutableList.copyOf(channels)));
         backendConn.write(packet.retain());
       } else if (PluginMessageUtil.isMcBrand(packet)) {
         String brand = PluginMessageUtil.readBrandMessage(packet.content());
@@ -339,43 +349,25 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
         }
 
         if (!player.getPhase().handle(player, packet, serverConn)) {
-          ChannelIdentifier id = server.getChannelRegistrar().getFromId(packet.getChannel());
-          if (id == null) {
-            // We don't have any plugins listening on this channel, process the packet now.
-            if (!player.getPhase().consideredComplete() || !serverConn.getPhase()
-                .consideredComplete()) {
-              // The client is trying to send messages too early. This is primarily caused by mods,
-              // but further aggravated by Velocity. To work around these issues, we will queue any
-              // non-FML handshake messages to be sent once the FML handshake has completed or the
-              // JoinGame packet has been received by the proxy, whichever comes first.
-              //
-              // We also need to make sure to retain these packets, so they can be flushed
-              // appropriately.
-              loginPluginMessages.add(packet.retain());
-            } else {
-              // The connection is ready, send the packet now.
-              backendConn.write(packet.retain());
-            }
-          } else {
-            byte[] copy = ByteBufUtil.getBytes(packet.content());
-            PluginMessageEvent event = new PluginMessageEvent(player, serverConn, id, copy);
-            server.getEventManager().fire(event).thenAcceptAsync(pme -> {
-              if (pme.getResult().isAllowed()) {
-                PluginMessagePacket message = new PluginMessagePacket(packet.getChannel(),
-                    Unpooled.wrappedBuffer(copy));
-                if (!player.getPhase().consideredComplete() || !serverConn.getPhase()
-                    .consideredComplete()) {
-                  // We're still processing the connection (see above), enqueue the packet for now.
-                  loginPluginMessages.add(message.retain());
-                } else {
-                  backendConn.write(message);
-                }
+          byte[] copy = ByteBufUtil.getBytes(packet.content());
+          String channel = packet.getChannel();
+          PluginMessageEvent event = new PluginMessageEvent(player, serverConn, channel.indexOf(':') == -1 ? new LegacyChannelIdentifier(channel) : MinecraftChannelIdentifier.from(channel), copy);
+          server.getEventManager().fire(event).thenAcceptAsync(pme -> {
+            if (pme.getResult().isAllowed()) {
+              PluginMessagePacket message = new PluginMessagePacket(packet.getChannel(),
+                      Unpooled.wrappedBuffer(copy));
+              if (!player.getPhase().consideredComplete() || !serverConn.getPhase()
+                      .consideredComplete()) {
+                // We're still processing the connection (see above), enqueue the packet for now.
+                loginPluginMessages.add(message.retain());
+              } else {
+                backendConn.write(message);
               }
-            }, backendConn.eventLoop()).exceptionally((ex) -> {
-              logger.error("Exception while handling plugin message packet for {}", player, ex);
-              return null;
-            });
-          }
+            }
+          }, backendConn.eventLoop()).exceptionally((ex) -> {
+            logger.error("Exception while handling plugin message packet for {}", player, ex);
+            return null;
+          });
         }
       }
     }
@@ -463,7 +455,11 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     }
 
     MinecraftConnection smc = serverConnection.getConnection();
-    if (smc != null && serverConnection.getPhase().consideredComplete()) {
+    final boolean stateAllowsForward = smc != null
+        && !smc.isClosed()
+        && serverConnection.getPhase().consideredComplete()
+        && smc.getState() == StateRegistry.PLAY;
+    if (stateAllowsForward) {
       if (packet instanceof PluginMessagePacket) {
         ((PluginMessagePacket) packet).retain();
       }
@@ -480,7 +476,11 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     }
 
     MinecraftConnection smc = serverConnection.getConnection();
-    if (smc != null && !smc.isClosed() && serverConnection.getPhase().consideredComplete()) {
+    final boolean stateAllowsForward = smc != null
+        && !smc.isClosed()
+        && serverConnection.getPhase().consideredComplete()
+        && smc.getState() == StateRegistry.PLAY;
+    if (stateAllowsForward) {
       smc.write(buf.retain());
     }
   }
@@ -492,14 +492,24 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
 
   @Override
   public void exception(Throwable throwable) {
-    player.disconnect(
-        Component.translatable("velocity.error.player-connection-error", NamedTextColor.RED));
+    player.disconnect(Component.translatable("velocity.error.player-connection-error", NamedTextColor.RED));
+    if (MinecraftDecoder.DEBUG) {
+      logger.info("Exception while handling packet for {}", player, throwable);
+    }
   }
 
   @Override
   public void writabilityChanged() {
     boolean writable = player.getConnection().getChannel().isWritable();
 
+    if (BACKPRESSURE_LOG) {
+      if (writable) {
+        logger.info("{} is writable, will auto-read backend connection data", player);
+      } else {
+        logger.info("{} is not writable, not auto-reading backend connection data", player);
+      }
+    }
+
     if (!writable) {
       // We might have packets queued from the server, so flush them now to free up memory. Make
       // sure to do it on a future invocation of the event loop, otherwise while the issue will
@@ -535,9 +545,13 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
 
       // Config state clears everything in the client. No need to clear later.
       spawned = false;
-      serverBossBars.clear();
       player.clearPlayerListHeaderAndFooterSilent();
       player.getTabList().clearAllSilent();
+      if (player.getProtocolVersion().noLessThan(ProtocolVersion.MINECRAFT_1_20_2)) {
+        player.getBossBarManager().dropPackets();
+      } else {
+        serverBossBars.clear();
+      }
     }
 
     player.switchToConfigState();
@@ -575,15 +589,20 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
       }
     }
 
-    // Remove previous boss bars. These don't get cleared when sending JoinGame, thus the need to
-    // track them.
-    for (UUID serverBossBar : serverBossBars) {
-      BossBarPacket deletePacket = new BossBarPacket();
-      deletePacket.setUuid(serverBossBar);
-      deletePacket.setAction(BossBarPacket.REMOVE);
-      player.getConnection().delayedWrite(deletePacket);
+    destination.setEntityId(joinGame.getEntityId()); // used for sound api
+    if (player.getProtocolVersion().noLessThan(ProtocolVersion.MINECRAFT_1_20_2)) {
+      player.getBossBarManager().sendBossBars();
+    } else {
+      // Remove previous boss bars. These don't get cleared when sending JoinGame (up until 1.20.2),
+      // thus the need to track them.
+      for (UUID serverBossBar : serverBossBars) {
+        BossBarPacket deletePacket = new BossBarPacket();
+        deletePacket.setUuid(serverBossBar);
+        deletePacket.setAction(BossBarPacket.REMOVE);
+        player.getConnection().delayedWrite(deletePacket);
+      }
+      serverBossBars.clear();
     }
-    serverBossBars.clear();
 
     // Tell the server about the proxy's plugin message channels.
     ProtocolVersion serverVersion = serverMc.getProtocolVersion();
@@ -694,23 +713,35 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
             return;
           }
 
-          List<Offer> offers = new ArrayList<>();
-          for (Suggestion suggestion : suggestions.getList()) {
-            String offer = suggestion.getText();
-            ComponentHolder tooltip = null;
-            if (suggestion.getTooltip() != null
-                && suggestion.getTooltip() instanceof VelocityBrigadierMessage) {
-              tooltip = new ComponentHolder(player.getProtocolVersion(),
-                  ((VelocityBrigadierMessage) suggestion.getTooltip()).asComponent());
+          int startPos = -1;
+          for (var suggestion : suggestions.getList()) {
+            if (startPos == -1 || startPos > suggestion.getRange().getStart()) {
+              startPos = suggestion.getRange().getStart();
             }
-            offers.add(new Offer(offer, tooltip));
           }
-          int startPos = packet.getCommand().lastIndexOf(' ') + 1;
+
           if (startPos > 0) {
+            List<Offer> offers = new ArrayList<>();
+            for (Suggestion suggestion : suggestions.getList()) {
+              String offer;
+              if (suggestion.getRange().getStart() == startPos) {
+                offer = suggestion.getText();
+              } else {
+                offer = command.substring(startPos, suggestion.getRange().getStart()) + suggestion.getText();
+              }
+              ComponentHolder tooltip = null;
+              if (suggestion.getTooltip() instanceof ComponentLike componentLike) {
+                tooltip = new ComponentHolder(player.getProtocolVersion(), componentLike.asComponent());
+              } else if (suggestion.getTooltip() != null) {
+                tooltip = new ComponentHolder(player.getProtocolVersion(), Component.text(suggestion.getTooltip().getString()));
+              }
+              offers.add(new Offer(offer, tooltip));
+            }
+
             TabCompleteResponsePacket resp = new TabCompleteResponsePacket();
             resp.setTransactionId(packet.getTransactionId());
-            resp.setStart(startPos);
-            resp.setLength(packet.getCommand().length() - startPos);
+            resp.setStart(startPos + 1);
+            resp.setLength(packet.getCommand().length() - startPos - 1);
             resp.getOffers().addAll(offers);
             player.getConnection().write(resp);
           }
@@ -765,10 +796,10 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
                 offer = offer.substring(command.length());
               }
               ComponentHolder tooltip = null;
-              if (suggestion.getTooltip() != null
-                  && suggestion.getTooltip() instanceof VelocityBrigadierMessage) {
-                tooltip = new ComponentHolder(player.getProtocolVersion(),
-                    ((VelocityBrigadierMessage) suggestion.getTooltip()).asComponent());
+              if (suggestion.getTooltip() instanceof ComponentLike componentLike) {
+                tooltip = new ComponentHolder(player.getProtocolVersion(), componentLike.asComponent());
+              } else if (suggestion.getTooltip() != null) {
+                tooltip = new ComponentHolder(player.getProtocolVersion(), Component.text(suggestion.getTooltip().getString()));
               }
               response.getOffers().add(new Offer(offer, tooltip));
             }

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ConnectedPlayer.java

@@ -62,6 +62,7 @@ import com.velocitypowered.proxy.adventure.VelocityBossBarImplementation;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.MinecraftConnectionAssociation;
 import com.velocitypowered.proxy.connection.backend.VelocityServerConnection;
+import com.velocitypowered.proxy.connection.player.bossbar.BossBarManager;
 import com.velocitypowered.proxy.connection.player.bundle.BundleDelimiterHandler;
 import com.velocitypowered.proxy.connection.player.resourcepack.VelocityResourcePackInfo;
 import com.velocitypowered.proxy.connection.player.resourcepack.handler.ResourcePackHandler;
@@ -73,6 +74,8 @@ import com.velocitypowered.proxy.protocol.netty.MinecraftEncoder;
 import com.velocitypowered.proxy.protocol.packet.BundleDelimiterPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientSettingsPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundCookieRequestPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundSoundEntityPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundStopSoundPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundStoreCookiePacket;
 import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
 import com.velocitypowered.proxy.protocol.packet.HeaderAndFooterPacket;
@@ -127,9 +130,12 @@ import net.kyori.adventure.pointer.PointersSupplier;
 import net.kyori.adventure.resource.ResourcePackInfoLike;
 import net.kyori.adventure.resource.ResourcePackRequest;
 import net.kyori.adventure.resource.ResourcePackRequestLike;
+import net.kyori.adventure.sound.Sound;
+import net.kyori.adventure.sound.SoundStop;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
 import net.kyori.adventure.text.logger.slf4j.ComponentLogger;
+import net.kyori.adventure.text.minimessage.translation.Argument;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
 import net.kyori.adventure.text.serializer.plain.PlainTextComponentSerializer;
 import net.kyori.adventure.title.Title.Times;
@@ -197,6 +203,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
   private @Nullable ClientSettingsPacket clientSettingsPacket;
   private volatile ChatQueue chatQueue;
   private final ChatBuilderFactory chatBuilderFactory;
+  private final BossBarManager bossBarManager;
 
   ConnectedPlayer(VelocityServer server, GameProfile profile, MinecraftConnection connection,
                   @Nullable InetSocketAddress virtualHost, @Nullable String rawVirtualHost, boolean onlineMode,
@@ -223,6 +230,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
     this.chatQueue = new ChatQueue(this);
     this.chatBuilderFactory = new ChatBuilderFactory(this.getProtocolVersion());
     this.resourcePackHandler = ResourcePackHandler.create(this, server);
+    this.bossBarManager = new BossBarManager(this);
   }
 
   /**
@@ -706,12 +714,12 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
     Component friendlyError;
     if (connectedServer != null && connectedServer.getServerInfo().equals(server.getServerInfo())) {
       friendlyError = Component.translatable("velocity.error.connected-server-error",
-          Component.text(server.getServerInfo().getName()));
+              Argument.string("server", server.getServerInfo().getName()));
     } else {
       logger.error("{}: unable to connect to server {}", this, server.getServerInfo().getName(),
           wrapped);
       friendlyError = Component.translatable("velocity.error.connecting-server-error",
-          Component.text(server.getServerInfo().getName()));
+              Argument.string("server", server.getServerInfo().getName()));
     }
     handleConnectionException(server, null, friendlyError.color(NamedTextColor.RED), safe);
   }
@@ -733,18 +741,22 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
     Component disconnectReason = disconnect.getReason().getComponent();
     String plainTextReason = PASS_THRU_TRANSLATE.serialize(disconnectReason);
     if (connectedServer != null && connectedServer.getServerInfo().equals(server.getServerInfo())) {
-      logger.info("{}: kicked from server {}: {}", this, server.getServerInfo().getName(),
-          plainTextReason);
+      if (this.server.getConfiguration().isLogPlayerConnections()) {
+        logger.info("{}: kicked from server {}: {}", this, server.getServerInfo().getName(),
+            plainTextReason);
+      }
       handleConnectionException(server, disconnectReason,
           Component.translatable("velocity.error.moved-to-new-server", NamedTextColor.RED,
-              Component.text(server.getServerInfo().getName()),
+              Argument.string("server", server.getServerInfo().getName()),
               disconnectReason), safe);
     } else {
-      logger.error("{}: disconnected while connecting to {}: {}", this,
-          server.getServerInfo().getName(), plainTextReason);
+      if (this.server.getConfiguration().isLogPlayerConnections()) {
+        logger.error("{}: disconnected while connecting to {}: {}", this,
+            server.getServerInfo().getName(), plainTextReason);
+      }
       handleConnectionException(server, disconnectReason,
           Component.translatable("velocity.error.cant-connect", NamedTextColor.RED,
-              Component.text(server.getServerInfo().getName()),
+              Argument.string("server", server.getServerInfo().getName()),
               disconnectReason), safe);
     }
   }
@@ -800,63 +812,56 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
         return;
       }
 
-      if (event.getResult() instanceof final DisconnectPlayer res) {
-        disconnect(res.getReasonComponent());
-      } else if (event.getResult() instanceof final RedirectPlayer res) {
-        createConnectionRequest(res.getServer(), previousConnection).connect()
-            .whenCompleteAsync((status, throwable) -> {
-              if (throwable != null) {
-                handleConnectionException(
-                    status != null ? status.getAttemptedConnection() : res.getServer(), throwable,
-                    true);
-                return;
-              }
+      switch (event.getResult()) {
+        case DisconnectPlayer res -> disconnect(res.getReasonComponent());
+        case RedirectPlayer res -> createConnectionRequest(res.getServer(), previousConnection).connect()
+                .whenCompleteAsync((status, throwable) -> {
+                  if (throwable != null) {
+                    handleConnectionException(res.getServer(), throwable, true);
+                    return;
+                  }
 
-              switch (status.getStatus()) {
-                // Impossible/nonsensical cases
-                case ALREADY_CONNECTED:
-                  logger.error("{}: already connected to {}", this,
-                      status.getAttemptedConnection().getServerInfo().getName());
-                  break;
-                case CONNECTION_IN_PROGRESS:
-                  // Fatal case
-                case CONNECTION_CANCELLED:
-                  Component fallbackMsg = res.getMessageComponent();
-                  if (fallbackMsg == null) {
-                    fallbackMsg = friendlyReason;
+                  switch (status.getStatus()) {
+                    // Impossible/nonsensical cases
+                    case ALREADY_CONNECTED -> logger.error("{}: already connected to {}", this,
+                            status.getAttemptedConnection().getServerInfo().getName());
+                    case CONNECTION_IN_PROGRESS, CONNECTION_CANCELLED -> {
+                      Component fallbackMsg = res.getMessageComponent();
+                      if (fallbackMsg == null) {
+                        fallbackMsg = friendlyReason;
+                      }
+                      disconnect(status.getReasonComponent().orElse(fallbackMsg));
+                    }
+                    case SERVER_DISCONNECTED -> {
+                      Component reason = status.getReasonComponent()
+                            .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
+                      handleConnectionException(res.getServer(),
+                            DisconnectPacket.create(reason, getProtocolVersion(), connection.getState()),
+                            ((Impl) status).isSafe());
+                    }
+                    case SUCCESS -> {
+                      Component requestedMessage = res.getMessageComponent();
+                      if (requestedMessage == null) {
+                        requestedMessage = friendlyReason;
+                      }
+                      if (requestedMessage != Component.empty()) {
+                        sendMessage(requestedMessage);
+                      }
+                    }
+                    default -> {
+                      // The only remaining value is successful (no need to do anything!)
+                    }
                   }
-                  disconnect(status.getReasonComponent().orElse(fallbackMsg));
-                  break;
-                case SERVER_DISCONNECTED:
-                  Component reason = status.getReasonComponent()
-                      .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
-                  handleConnectionException(res.getServer(),
-                      DisconnectPacket.create(reason, getProtocolVersion(), connection.getState()),
-                      ((Impl) status).isSafe());
-                  break;
-                case SUCCESS:
-                  Component requestedMessage = res.getMessageComponent();
-                  if (requestedMessage == null) {
-                    requestedMessage = friendlyReason;
-                  }
-                  if (requestedMessage != Component.empty()) {
-                    sendMessage(requestedMessage);
-                  }
-                  break;
-                default:
-                  // The only remaining value is successful (no need to do anything!)
-                  break;
-              }
-            }, connection.eventLoop());
-      } else if (event.getResult() instanceof final Notify res) {
-        if (event.kickedDuringServerConnect() && previousConnection != null) {
-          sendMessage(res.getMessageComponent());
-        } else {
-          disconnect(res.getMessageComponent());
+                }, connection.eventLoop());
+        case Notify res -> {
+          if (event.kickedDuringServerConnect() && previousConnection != null) {
+            sendMessage(res.getMessageComponent());
+          } else {
+            disconnect(res.getMessageComponent());
+          }
         }
-      } else {
         // In case someone gets creative, assume we want to disconnect the player.
-        disconnect(friendlyReason);
+        default -> disconnect(friendlyReason);
       }
     }, connection.eventLoop());
   }
@@ -1038,6 +1043,50 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
     this.clientBrand = clientBrand;
   }
 
+  @Override
+  public void playSound(@NotNull Sound sound, @NotNull Sound.Emitter emitter) {
+    Preconditions.checkNotNull(sound, "sound");
+    Preconditions.checkNotNull(emitter, "emitter");
+    VelocityServerConnection soundTargetServerConn = getConnectedServer();
+    if (getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_19_3)
+        || connection.getState() != StateRegistry.PLAY
+        || soundTargetServerConn == null
+        || (sound.source() == Sound.Source.UI
+            && getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_21_5))) {
+      return;
+    }
+
+    VelocityServerConnection soundEmitterServerConn;
+    if (emitter == Sound.Emitter.self()) {
+      soundEmitterServerConn = soundTargetServerConn;
+    } else if (emitter instanceof ConnectedPlayer player) {
+      if ((soundEmitterServerConn = player.getConnectedServer()) == null) {
+        return;
+      }
+
+      if (!soundEmitterServerConn.getServer().equals(soundTargetServerConn.getServer())) {
+        return;
+      }
+    } else {
+      return;
+    }
+
+    connection.write(new ClientboundSoundEntityPacket(sound, null, soundEmitterServerConn.getEntityId()));
+  }
+
+  @Override
+  public void stopSound(@NotNull SoundStop stop) {
+    Preconditions.checkNotNull(stop, "stop");
+    if (getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_19_3)
+        || connection.getState() != StateRegistry.PLAY
+        || (stop.source() == Sound.Source.UI
+            && getProtocolVersion().lessThan(ProtocolVersion.MINECRAFT_1_21_5))) {
+      return;
+    }
+
+    connection.write(new ClientboundStopSoundPacket(stop));
+  }
+
   @Override
   public void transferToHost(final InetSocketAddress address) {
     Preconditions.checkNotNull(address);
@@ -1300,11 +1349,17 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
       final Long sentTime = serverConnection.getPendingPings().remove(packet.getRandomId());
       if (sentTime != null) {
         final MinecraftConnection smc = serverConnection.getConnection();
-        if (smc != null) {
+        final StateRegistry clientState = connection.getState();
+        final boolean stateAllowsForward = smc != null
+            && !smc.isClosed()
+            && clientState == smc.getState()
+            && (clientState == StateRegistry.CONFIG || clientState == StateRegistry.PLAY);
+        if (stateAllowsForward) {
           setPing(TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - sentTime));
           smc.write(packet);
-          return true;
         }
+        // We removed this, and so this is ours
+        return true;
       }
     }
     return false;
@@ -1314,7 +1369,8 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
    * Switches the connection to the client into config state.
    */
   public void switchToConfigState() {
-    server.getEventManager().fire(new PlayerEnterConfigurationEvent(this, getConnectionInFlightOrConnectedServer()))
+    final VelocityServerConnection targetServer = getConnectionInFlightOrConnectedServer();
+    server.getEventManager().fire(new PlayerEnterConfigurationEvent(this, targetServer))
         .completeOnTimeout(null, 5, TimeUnit.SECONDS).thenRunAsync(() -> {
           // if the connection was closed earlier, there is a risk that the player is no longer connected
           if (!connection.getChannel().isActive()) {
@@ -1329,7 +1385,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
           connection.pendingConfigurationSwitch = true;
           connection.getChannel().pipeline().get(MinecraftEncoder.class).setState(StateRegistry.CONFIG);
           // Make sure we don't send any play packets to the player after update start
-          connection.addPlayPacketQueueHandler();
+          connection.addPlayPacketQueueOutboundHandler();
         }, connection.eventLoop()).exceptionally((ex) -> {
           logger.error("Error switching player connection to config state", ex);
           return null;
@@ -1379,6 +1435,10 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
     return handshakeIntent;
   }
 
+  public BossBarManager getBossBarManager() {
+    return bossBarManager;
+  }
+
   private final class ConnectionRequestBuilderImpl implements ConnectionRequestBuilder {
 
     private final RegisteredServer toConnect;
@@ -1438,7 +1498,16 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
           VelocityServerConnection con =
               new VelocityServerConnection(vrs, previousServer, ConnectedPlayer.this, server);
           connectionInFlight = con;
-          return con.connect().whenCompleteAsync((result, exception) -> this.resetIfInFlightIs(con),
+
+          return con.connect().whenCompleteAsync((result, exception) -> {
+            if (result != null && !result.isSuccessful() && !result.isSafe()) {
+              handleConnectionException(result.getAttemptedConnection(),
+                  // The only way for the reason to be null is if the result is safe
+                  DisconnectPacket.create(result.getReasonComponent().orElseThrow(),
+                      getProtocolVersion(), connection.getState()), false);
+            }
+            this.resetIfInFlightIs(con);
+          },
               connection.eventLoop());
         }, connection.eventLoop());
       });
@@ -1452,22 +1521,14 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player,
 
     @Override
     public CompletableFuture<Result> connect() {
-      return this.internalConnect().whenCompleteAsync((status, throwable) -> {
-        if (status != null && !status.isSuccessful()) {
-          if (!status.isSafe()) {
-            handleConnectionException(status.getAttemptedConnection(), throwable, false);
-          }
-        }
-      }, connection.eventLoop()).thenApply(x -> x);
+      return this.internalConnect().thenApply(x -> x);
     }
 
     @Override
     public CompletableFuture<Boolean> connectWithIndication() {
       return internalConnect().whenCompleteAsync((status, throwable) -> {
         if (throwable != null) {
-          // TODO: The exception handling from this is not very good. Find a better way.
-          handleConnectionException(status != null ? status.getAttemptedConnection() : toConnect,
-              throwable, true);
+          handleConnectionException(toConnect, throwable, true);
           return;
         }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/client/HandshakeSessionHandler.java

@@ -127,10 +127,10 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     if (!handshake.getProtocolVersion().isSupported()) {
       // Bump connection into correct protocol state so that we can send the disconnect packet.
       connection.setState(StateRegistry.LOGIN);
-      ic.disconnectQuietly(Component.translatable()
-              .key("multiplayer.disconnect.outdated_client")
-              .arguments(Component.text(ProtocolVersion.SUPPORTED_VERSION_STRING))
-              .build());
+      ic.disconnectQuietly(Component.translatable(
+          "multiplayer.disconnect.outdated_client",
+          Component.text(ProtocolVersion.SUPPORTED_VERSION_STRING)
+      ));
       return;
     }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/client/InitialLoginSessionHandler.java

@@ -152,7 +152,7 @@ public class InitialLoginSessionHandler implements MinecraftSessionHandler {
           } else {
             mcConnection.setActiveSessionHandler(StateRegistry.LOGIN,
                 new AuthSessionHandler(server, inbound,
-                    GameProfile.forOfflinePlayer(login.getUsername()), false));
+                    GameProfile.forOfflinePlayer(login.getUsername()), false, null));
           }
         });
       });
@@ -214,6 +214,7 @@ public class InitialLoginSessionHandler implements MinecraftSessionHandler {
                       server.getVersion().getName() + "/" + server.getVersion().getVersion())
               .uri(URI.create(url))
               .build();
+      //noinspection resource
       final HttpClient httpClient = server.createHttpClient();
       httpClient.sendAsync(httpRequest, HttpResponse.BodyHandlers.ofString())
           .whenCompleteAsync((response, throwable) -> {
@@ -254,7 +255,7 @@ public class InitialLoginSessionHandler implements MinecraftSessionHandler {
               }
               // All went well, initialize the session.
               mcConnection.setActiveSessionHandler(StateRegistry.LOGIN,
-                  new AuthSessionHandler(server, inbound, profile, true));
+                  new AuthSessionHandler(server, inbound, profile, true, serverId));
             } else if (response.statusCode() == 204) {
               // Apparently an offline-mode user logged onto this online-mode proxy.
               inbound.disconnect(
@@ -268,14 +269,12 @@ public class InitialLoginSessionHandler implements MinecraftSessionHandler {
             }
           }, mcConnection.eventLoop())
           .thenRun(() -> {
-            if (httpClient instanceof final AutoCloseable closeable) {
-              try {
-                closeable.close();
-              } catch (Exception e) {
-                // In Java 21, the HttpClient does not throw any Exception
-                // when trying to clean its resources, so this should not happen
-                logger.error("An unknown error occurred while trying to close an HttpClient", e);
-              }
+            try {
+              httpClient.close();
+            } catch (Exception e) {
+              // In Java 21, the HttpClient does not throw any Exception
+              // when trying to clean its resources, so this should not happen
+              logger.error("An unknown error occurred while trying to close an HttpClient", e);
             }
           });
     } catch (GeneralSecurityException e) {

proxy/src/main/java/com/velocitypowered/proxy/connection/player/bossbar/BossBarManager.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2019-2023 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.connection.player.bossbar;
+
+import com.velocitypowered.proxy.adventure.VelocityBossBarImplementation;
+import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
+import com.velocitypowered.proxy.protocol.packet.BossBarPacket;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Handles dropping and resending boss bar packets on versions 1.20.2 and newer because the client now
+ * deletes all boss bars during the login phase, and sending update packets would cause the client to be disconnected.
+ */
+public final class BossBarManager {
+
+  private final ConnectedPlayer player;
+  private final Set<VelocityBossBarImplementation> bossBars = new HashSet<>();
+
+  private boolean dropPackets = false;
+
+  public BossBarManager(ConnectedPlayer player) {
+    this.player = player;
+  }
+
+  /**
+   * Records the specified boss bar to be re-sent when a player changes server, and sends the update packet
+   * if the client is able to receive it and not be disconnected.
+   */
+  public synchronized void writeUpdate(VelocityBossBarImplementation bar, BossBarPacket packet) {
+    this.bossBars.add(bar);
+    if (!this.dropPackets) {
+      this.player.getConnection().write(packet);
+    }
+  }
+
+  /**
+   * Removes the specified boss bar from the player to ensure it is not re-sent.
+   */
+  public synchronized void remove(VelocityBossBarImplementation bar, BossBarPacket packet) {
+    this.bossBars.remove(bar);
+    if (!this.dropPackets) {
+      this.player.getConnection().write(packet);
+    }
+  }
+
+  /**
+   * Re-creates the boss bars the player can see with any updates that may have occurred in the meantime,
+   * and allows update packets for those boss bars to be sent.
+   */
+  public synchronized void sendBossBars() {
+    for (VelocityBossBarImplementation bossBar : bossBars) {
+      bossBar.createDirect(player);
+    }
+    this.dropPackets = false;
+  }
+
+  /**
+   * Prevents the player from receiving boss bar update packets while logging in to a new server.
+   */
+  public synchronized void dropPackets() {
+    this.dropPackets = true;
+  }
+}

proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/handler/ModernResourcePackHandler.java

@@ -94,7 +94,7 @@ public final class ModernResourcePackHandler extends ResourcePackHandler {
         this.outstandingResourcePacks.get(info.getId());
     outstandingResourcePacks.add(info);
     if (outstandingResourcePacks.size() == 1) {
-      tickResourcePackQueue(outstandingResourcePacks.get(0).getId());
+      tickResourcePackQueue(outstandingResourcePacks.getFirst().getId());
     }
   }
 
@@ -111,7 +111,7 @@ public final class ModernResourcePackHandler extends ResourcePackHandler {
     final List<ResourcePackInfo> outstandingResourcePacks =
         this.outstandingResourcePacks.get(uuid);
     if (!outstandingResourcePacks.isEmpty()) {
-      sendResourcePackRequestPacket(outstandingResourcePacks.get(0));
+      sendResourcePackRequestPacket(outstandingResourcePacks.getFirst());
     }
   }
 
@@ -124,7 +124,7 @@ public final class ModernResourcePackHandler extends ResourcePackHandler {
         this.outstandingResourcePacks.get(uuid);
     final boolean peek = bundle.status().isIntermediate();
     final ResourcePackInfo queued = outstandingResourcePacks.isEmpty() ? null :
-        peek ? outstandingResourcePacks.get(0) : outstandingResourcePacks.remove(0);
+        peek ? outstandingResourcePacks.getFirst() : outstandingResourcePacks.removeFirst();
 
     server.getEventManager()
             .fire(new PlayerResourcePackStatusEvent(this.player, uuid, bundle.status(), queued))

proxy/src/main/java/com/velocitypowered/proxy/connection/player/resourcepack/handler/ResourcePackHandler.java

@@ -111,7 +111,7 @@ public abstract sealed class ResourcePackHandler
     }
     request.setRequired(queued.getShouldForce());
     request.setPrompt(queued.getPrompt() == null ? null :
-            new ComponentHolder(player.getProtocolVersion(), queued.getPrompt()));
+            new ComponentHolder(player.getProtocolVersion(), player.translateMessage(queued.getPrompt())));
 
     player.getConnection().write(request);
   }

proxy/src/main/java/com/velocitypowered/proxy/connection/util/ServerListPingHandler.java

@@ -36,6 +36,7 @@ import java.util.Locale;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import java.util.stream.Collectors;
+import net.kyori.adventure.text.Component;
 
 /**
  * Common utilities for handling server list ping results.
@@ -99,58 +100,60 @@ public class ServerListPingHandler {
 
     CompletableFuture<List<ServerPing>> pingResponses = CompletableFutures.successfulAsList(pings,
         (ex) -> fallback);
-    switch (mode) {
-      case ALL:
-        return pingResponses.thenApply(responses -> {
-          // Find the first non-fallback
-          for (ServerPing response : responses) {
-            if (response == fallback) {
-              continue;
-            }
-            return response;
+    return switch (mode) {
+      case ALL -> pingResponses.thenApply(responses -> {
+        // Find the first non-fallback
+        for (ServerPing response : responses) {
+          if (response == fallback) {
+            continue;
           }
-          return fallback;
-        });
-      case MODS:
-        return pingResponses.thenApply(responses -> {
-          // Find the first non-fallback that contains a mod list
-          for (ServerPing response : responses) {
-            if (response == fallback) {
-              continue;
-            }
-            Optional<ModInfo> modInfo = response.getModinfo();
-            if (modInfo.isPresent()) {
-              return fallback.asBuilder().mods(modInfo.get()).build();
-            }
-          }
-          return fallback;
-        });
-      case DESCRIPTION:
-        return pingResponses.thenApply(responses -> {
-          // Find the first non-fallback. If it includes a modlist, add it too.
-          for (ServerPing response : responses) {
-            if (response == fallback) {
-              continue;
-            }
 
-            if (response.getDescriptionComponent() == null) {
-              continue;
-            }
-
-            return new ServerPing(
-                fallback.getVersion(),
-                fallback.getPlayers().orElse(null),
-                response.getDescriptionComponent(),
-                fallback.getFavicon().orElse(null),
-                response.getModinfo().orElse(null)
-            );
+          if (response.getDescriptionComponent() == null) {
+            return response.asBuilder()
+                .description(Component.empty())
+                .build();
           }
-          return fallback;
-        });
+
+          return response;
+        }
+        return fallback;
+      });
+      case MODS -> pingResponses.thenApply(responses -> {
+        // Find the first non-fallback that contains a mod list
+        for (ServerPing response : responses) {
+          if (response == fallback) {
+            continue;
+          }
+          Optional<ModInfo> modInfo = response.getModinfo();
+          if (modInfo.isPresent()) {
+            return fallback.asBuilder().mods(modInfo.get()).build();
+          }
+        }
+        return fallback;
+      });
+      case DESCRIPTION -> pingResponses.thenApply(responses -> {
+        // Find the first non-fallback. If it includes a modlist, add it too.
+        for (ServerPing response : responses) {
+          if (response == fallback) {
+            continue;
+          }
+          if (response.getDescriptionComponent() == null) {
+            continue;
+          }
+
+          return new ServerPing(
+              fallback.getVersion(),
+              fallback.getPlayers().orElse(null),
+              response.getDescriptionComponent(),
+              fallback.getFavicon().orElse(null),
+              response.getModinfo().orElse(null)
+          );
+        }
+        return fallback;
+      });
       // Not possible, but covered for completeness.
-      default:
-        return CompletableFuture.completedFuture(fallback);
-    }
+      default -> CompletableFuture.completedFuture(fallback);
+    };
   }
 
   /**

proxy/src/main/java/com/velocitypowered/proxy/console/VelocityConsole.java

@@ -33,6 +33,7 @@ import net.kyori.adventure.permission.PermissionChecker;
 import net.kyori.adventure.platform.facet.FacetPointers;
 import net.kyori.adventure.platform.facet.FacetPointers.Type;
 import net.kyori.adventure.pointer.Pointers;
+import net.kyori.adventure.pointer.PointersSupplier;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
 import net.kyori.adventure.text.logger.slf4j.ComponentLogger;
@@ -59,11 +60,11 @@ public final class VelocityConsole extends SimpleTerminalConsole implements Cons
 
   private final VelocityServer server;
   private PermissionFunction permissionFunction = ALWAYS_TRUE;
-  private final @NotNull Pointers pointers = ConsoleCommandSource.super.pointers().toBuilder()
-      .withDynamic(PermissionChecker.POINTER, this::getPermissionChecker)
-      .withDynamic(Identity.LOCALE, () -> ClosestLocaleMatcher.INSTANCE
+  private static final @NotNull PointersSupplier<VelocityConsole> POINTERS = PointersSupplier.<VelocityConsole>builder()
+      .resolving(PermissionChecker.POINTER, VelocityConsole::getPermissionChecker)
+      .resolving(Identity.LOCALE, (console) -> ClosestLocaleMatcher.INSTANCE
           .lookupClosest(Locale.getDefault()))
-      .withStatic(FacetPointers.TYPE, Type.CONSOLE)
+      .resolving(FacetPointers.TYPE, (console) -> Type.CONSOLE)
       .build();
 
   public VelocityConsole(VelocityServer server) {
@@ -136,6 +137,10 @@ public final class VelocityConsole extends SimpleTerminalConsole implements Cons
       if (!this.server.getCommandManager().executeAsync(this, command).join()) {
         sendMessage(Component.translatable("velocity.command.command-does-not-exist",
             NamedTextColor.RED));
+        return;
+      }
+      if (server.getConfiguration().isLogCommandExecutions()) {
+        logger.info("CONSOLE -> executed command /{}", command);
       }
     } catch (Exception e) {
       logger.error("An error occurred while running this command.", e);
@@ -149,6 +154,6 @@ public final class VelocityConsole extends SimpleTerminalConsole implements Cons
 
   @Override
   public @NotNull Pointers pointers() {
-    return pointers;
+    return POINTERS.view(this);
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/network/ServerChannelInitializer.java

@@ -26,8 +26,10 @@ import static com.velocitypowered.proxy.network.Connections.MINECRAFT_ENCODER;
 import static com.velocitypowered.proxy.network.Connections.READ_TIMEOUT;
 
 import com.velocitypowered.proxy.VelocityServer;
+import com.velocitypowered.proxy.config.VelocityConfiguration;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.client.HandshakeSessionHandler;
+import com.velocitypowered.proxy.network.limiter.SimpleBytesPerSecondLimiter;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
 import com.velocitypowered.proxy.protocol.netty.LegacyPingDecoder;
@@ -72,6 +74,17 @@ public class ServerChannelInitializer extends ChannelInitializer<Channel> {
         new HandshakeSessionHandler(connection, this.server));
     ch.pipeline().addLast(Connections.HANDLER, connection);
 
+    VelocityConfiguration.PacketLimiterConfig packetLimiterConfig =
+        server.getConfiguration().getPacketLimiterConfig();
+    int configuredInterval = packetLimiterConfig.interval();
+    int configuredPacketsPerSecond = packetLimiterConfig.pps();
+    int configuredBytes = packetLimiterConfig.bytes();
+
+    if (configuredInterval > 0 && (configuredBytes > 0 ||  configuredPacketsPerSecond > 0)) {
+      ch.pipeline().get(MinecraftVarintFrameDecoder.class).setPacketLimiter(
+          new SimpleBytesPerSecondLimiter(configuredPacketsPerSecond, configuredBytes, configuredInterval)
+      );
+    }
     if (this.server.getConfiguration().isProxyProtocol()) {
       ch.pipeline().addFirst(new HAProxyMessageDecoder());
     }

proxy/src/main/java/com/velocitypowered/proxy/network/TransportType.java

@@ -116,7 +116,7 @@ public enum TransportType {
       return NIO;
     }
 
-    if (IoUring.isAvailable() && !Boolean.getBoolean("velocity.disable-iouring-transport")) {
+    if (IoUring.isAvailable() && Boolean.getBoolean("velocity.enable-iouring-transport")) {
       return IO_URING;
     }
 

proxy/src/main/java/com/velocitypowered/proxy/network/limiter/PacketLimiter.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.network.limiter;
+
+/**
+ * PacketLimiter enforces a limit on the number of bytes processed over a time window.
+ * Implementations should be thread-safe.
+ */
+public interface PacketLimiter {
+  /**
+   * Attempts to record the specified number of bytes within the current window.
+   *
+   * @param bytes the number of bytes to record
+   * @return true if the bytes are allowed and recorded; false if the limit would be exceeded
+   */
+  boolean account(int bytes);
+}

proxy/src/main/java/com/velocitypowered/proxy/network/limiter/SimpleBytesPerSecondLimiter.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.network.limiter;
+
+import com.velocitypowered.proxy.util.IntervalledCounter;
+import org.jspecify.annotations.Nullable;
+
+/**
+ * A moving-window limiter over a configurable number of seconds.
+ * It enforces both packets-per-second and average bytes-per-second limits.
+ * The effective cap over the full window equals limitPerSecond * windowSeconds.
+ */
+public final class SimpleBytesPerSecondLimiter implements PacketLimiter {
+  @Nullable
+  private final IntervalledCounter bytesCounter;
+  @Nullable
+  private final IntervalledCounter packetsCounter;
+  private final int packetsPerSecond;
+  private final int bytesPerSecond;
+
+  /**
+   * Creates a new SimpleBytesPerSecondLimiter.
+   *
+   * @param packetsPerSecond maximum average packets per second allowed (> 0)
+   * @param bytesPerSecond maximum average bytes per second allowed (> 0)
+   * @param windowSeconds number of seconds in the moving window (> 0)
+   */
+  public SimpleBytesPerSecondLimiter(int packetsPerSecond, int bytesPerSecond, int windowSeconds) {
+    this.packetsPerSecond = packetsPerSecond;
+    if (windowSeconds <= 0) {
+      throw new IllegalArgumentException("windowSeconds must be > 0");
+    }
+    this.bytesPerSecond = bytesPerSecond;
+    this.packetsCounter = packetsPerSecond > 0 ? new IntervalledCounter((long) (windowSeconds * 1.0e9)) : null;
+    this.bytesCounter = bytesPerSecond > 0 ? new IntervalledCounter((long) (windowSeconds * 1.0e9)) : null;
+
+  }
+
+  /**
+   * Records the given payload length as one packet and returns whether it is allowed.
+   */
+  @SuppressWarnings("RedundantIfStatement")
+  @Override
+  public boolean account(int bytes) {
+    long currTime = System.nanoTime();
+    if (packetsCounter != null) {
+      packetsCounter.updateAndAdd(1, currTime);
+      if (packetsCounter.getRate() > packetsPerSecond) {
+        return false;
+      }
+    }
+
+    if (bytesCounter != null) {
+      bytesCounter.updateAndAdd(bytes, currTime);
+      if (bytesCounter.getRate() > bytesPerSecond) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+}

proxy/src/main/java/com/velocitypowered/proxy/network/netty/SeparatePoolInetNameResolver.java

@@ -71,7 +71,7 @@ public final class SeparatePoolInetNameResolver extends InetNameResolver {
   protected void doResolve(String inetHost, Promise<InetAddress> promise) throws Exception {
     List<InetAddress> addresses = cache.getIfPresent(inetHost);
     if (addresses != null) {
-      promise.trySuccess(addresses.get(0));
+      promise.trySuccess(addresses.getFirst());
       return;
     }
 

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/JavaPluginLoader.java

@@ -83,7 +83,7 @@ public class JavaPluginLoader implements PluginLoader {
 
   @Override
   public PluginDescription createPluginFromCandidate(PluginDescription candidate) throws Exception {
-    if (!(candidate instanceof JavaVelocityPluginDescriptionCandidate)) {
+    if (!(candidate instanceof JavaVelocityPluginDescriptionCandidate candidateInst)) {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
     }
 
@@ -93,8 +93,6 @@ public class JavaPluginLoader implements PluginLoader {
     PluginClassLoader loader = new PluginClassLoader(new URL[]{pluginJarUrl});
     loader.addToClassloaders();
 
-    JavaVelocityPluginDescriptionCandidate candidateInst =
-        (JavaVelocityPluginDescriptionCandidate) candidate;
     Class<?> mainClass = loader.loadClass(candidateInst.getMainClass());
     return createDescription(candidateInst, mainClass);
   }
@@ -102,11 +100,10 @@ public class JavaPluginLoader implements PluginLoader {
   @Override
   public Module createModule(PluginContainer container) {
     PluginDescription description = container.getDescription();
-    if (!(description instanceof JavaVelocityPluginDescription)) {
+    if (!(description instanceof JavaVelocityPluginDescription javaDescription)) {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
     }
 
-    JavaVelocityPluginDescription javaDescription = (JavaVelocityPluginDescription) description;
     Optional<Path> source = javaDescription.getSource();
 
     if (source.isEmpty()) {
@@ -118,24 +115,23 @@ public class JavaPluginLoader implements PluginLoader {
 
   @Override
   public void createPlugin(PluginContainer container, Module... modules) {
-    if (!(container instanceof VelocityPluginContainer)) {
+    if (!(container instanceof VelocityPluginContainer pluginContainer)) {
       throw new IllegalArgumentException("Container provided isn't of the Java plugin loader");
     }
-    PluginDescription description = container.getDescription();
-    if (!(description instanceof JavaVelocityPluginDescription)) {
+    PluginDescription description = pluginContainer.getDescription();
+    if (!(description instanceof JavaVelocityPluginDescription javaPluginDescription)) {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
     }
 
     Injector injector = Guice.createInjector(modules);
-    Object instance = injector
-        .getInstance(((JavaVelocityPluginDescription) description).getMainClass());
+    Object instance = injector.getInstance(javaPluginDescription.getMainClass());
 
     if (instance == null) {
       throw new IllegalStateException(
           "Got nothing from injector for plugin " + description.getId());
     }
 
-    ((VelocityPluginContainer) container).setInstance(instance);
+    pluginContainer.setInstance(instance);
   }
 
   private Optional<SerializedPluginDescription> getSerializedPluginInfo(Path source)
@@ -145,22 +141,23 @@ public class JavaPluginLoader implements PluginLoader {
         new BufferedInputStream(Files.newInputStream(source)))) {
       JarEntry entry;
       while ((entry = in.getNextJarEntry()) != null) {
-        if (entry.getName().equals("velocity-plugin.json")) {
-          try (Reader pluginInfoReader = new InputStreamReader(in, StandardCharsets.UTF_8)) {
-            return Optional.of(VelocityServer.GENERAL_GSON.fromJson(pluginInfoReader,
-                SerializedPluginDescription.class));
+        switch (entry.getName()) {
+          case "velocity-plugin.json" -> {
+            try (Reader pluginInfoReader = new InputStreamReader(in, StandardCharsets.UTF_8)) {
+              return Optional.of(VelocityServer.GENERAL_GSON.fromJson(pluginInfoReader,
+                  SerializedPluginDescription.class));
+            }
+          }
+          case "paper-plugin.yml", "plugin.yml", "bungee.yml" -> foundBungeeBukkitPluginFile = true;
+          default -> {
           }
-        }
-
-        if (entry.getName().equals("plugin.yml") || entry.getName().equals("bungee.yml")) {
-          foundBungeeBukkitPluginFile = true;
         }
       }
 
       if (foundBungeeBukkitPluginFile) {
         throw new InvalidPluginException("The plugin file " + source.getFileName() + " appears to "
-            + "be a Bukkit or BungeeCord plugin. Velocity does not support Bukkit or BungeeCord "
-            + "plugins.");
+            + "be a Paper, Bukkit or BungeeCord plugin. Velocity does not support plugins from these "
+            + "platforms.");
       }
 
       return Optional.empty();

proxy/src/main/java/com/velocitypowered/proxy/protocol/MinecraftPacket.java

@@ -32,13 +32,18 @@ public interface MinecraftPacket {
 
   boolean handle(MinecraftSessionHandler handler);
 
-  default int expectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
+  default int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
       ProtocolVersion version) {
     return -1;
   }
 
-  default int expectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction,
+  default int decodeExpectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction,
       ProtocolVersion version) {
     return 0;
   }
+
+  default int encodeSizeHint(ProtocolUtils.Direction direction,
+      ProtocolVersion version) {
+    return -1;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/ProtocolUtils.java

@@ -36,7 +36,9 @@ import io.netty.handler.codec.EncoderException;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.UUID;
 import net.kyori.adventure.key.Key;
 import net.kyori.adventure.nbt.BinaryTag;
@@ -44,6 +46,7 @@ import net.kyori.adventure.nbt.BinaryTagIO;
 import net.kyori.adventure.nbt.BinaryTagType;
 import net.kyori.adventure.nbt.BinaryTagTypes;
 import net.kyori.adventure.nbt.CompoundBinaryTag;
+import net.kyori.adventure.sound.Sound;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.kyori.adventure.text.serializer.json.JSONOptions;
 import net.kyori.adventure.text.serializer.json.legacyimpl.NBTLegacyHoverEventSerializer;
@@ -61,6 +64,8 @@ public enum ProtocolUtils {
           .legacyHoverEventSerializer(NBTLegacyHoverEventSerializer.get())
           .options(
               OptionSchema.globalSchema().stateBuilder()
+              // general options
+              .value(JSONOptions.EMIT_CLICK_URL_HTTPS, Boolean.TRUE)
               // before 1.16
               .value(JSONOptions.EMIT_RGB, Boolean.FALSE)
               .value(JSONOptions.EMIT_HOVER_EVENT_TYPE, JSONOptions.HoverEventValueMode.VALUE_FIELD)
@@ -69,6 +74,8 @@ public enum ProtocolUtils {
               .value(JSONOptions.EMIT_COMPACT_TEXT_COMPONENT, Boolean.FALSE)
               .value(JSONOptions.EMIT_HOVER_SHOW_ENTITY_ID_AS_INT_ARRAY, Boolean.FALSE)
               .value(JSONOptions.VALIDATE_STRICT_EVENTS, Boolean.FALSE)
+              // before 1.21.5
+              .value(JSONOptions.EMIT_CHANGE_PAGE_CLICK_EVENT_PAGE_AS_STRING, Boolean.TRUE)
               .build()
           )
           .build();
@@ -77,6 +84,8 @@ public enum ProtocolUtils {
           .legacyHoverEventSerializer(NBTLegacyHoverEventSerializer.get())
           .options(
               OptionSchema.globalSchema().stateBuilder()
+              // general options
+              .value(JSONOptions.EMIT_CLICK_URL_HTTPS, Boolean.TRUE)
               // after 1.16
               .value(JSONOptions.EMIT_RGB, Boolean.TRUE)
               .value(JSONOptions.EMIT_HOVER_EVENT_TYPE, JSONOptions.HoverEventValueMode.CAMEL_CASE)
@@ -86,6 +95,8 @@ public enum ProtocolUtils {
               .value(JSONOptions.EMIT_COMPACT_TEXT_COMPONENT, Boolean.FALSE)
               .value(JSONOptions.EMIT_HOVER_SHOW_ENTITY_ID_AS_INT_ARRAY, Boolean.FALSE)
               .value(JSONOptions.VALIDATE_STRICT_EVENTS, Boolean.FALSE)
+              // before 1.21.5
+              .value(JSONOptions.EMIT_CHANGE_PAGE_CLICK_EVENT_PAGE_AS_STRING, Boolean.TRUE)
               .build()
           )
           .build();
@@ -94,6 +105,8 @@ public enum ProtocolUtils {
           .legacyHoverEventSerializer(NBTLegacyHoverEventSerializer.get())
           .options(
               OptionSchema.globalSchema().stateBuilder()
+              // general options
+              .value(JSONOptions.EMIT_CLICK_URL_HTTPS, Boolean.TRUE)
               // after 1.16
               .value(JSONOptions.EMIT_RGB, Boolean.TRUE)
               .value(JSONOptions.EMIT_HOVER_EVENT_TYPE, JSONOptions.HoverEventValueMode.CAMEL_CASE)
@@ -103,6 +116,8 @@ public enum ProtocolUtils {
               .value(JSONOptions.EMIT_COMPACT_TEXT_COMPONENT, Boolean.TRUE)
               .value(JSONOptions.EMIT_HOVER_SHOW_ENTITY_ID_AS_INT_ARRAY, Boolean.TRUE)
               .value(JSONOptions.VALIDATE_STRICT_EVENTS, Boolean.TRUE)
+              // before 1.21.5
+              .value(JSONOptions.EMIT_CHANGE_PAGE_CLICK_EVENT_PAGE_AS_STRING, Boolean.TRUE)
               .build()
           )
           .build();
@@ -111,6 +126,8 @@ public enum ProtocolUtils {
           .legacyHoverEventSerializer(NBTLegacyHoverEventSerializer.get())
           .options(
               OptionSchema.globalSchema().stateBuilder()
+              // general options
+              .value(JSONOptions.EMIT_CLICK_URL_HTTPS, Boolean.TRUE)
               // after 1.16
               .value(JSONOptions.EMIT_RGB, Boolean.TRUE)
               .value(JSONOptions.EMIT_HOVER_EVENT_TYPE, JSONOptions.HoverEventValueMode.SNAKE_CASE)
@@ -121,6 +138,7 @@ public enum ProtocolUtils {
               // after 1.21.5
               .value(JSONOptions.EMIT_HOVER_SHOW_ENTITY_KEY_AS_TYPE_AND_UUID_AS_ID, Boolean.FALSE)
               .value(JSONOptions.VALIDATE_STRICT_EVENTS, Boolean.TRUE)
+              .value(JSONOptions.EMIT_CHANGE_PAGE_CLICK_EVENT_PAGE_AS_STRING, Boolean.FALSE)
               .build()
           )
           .build();
@@ -134,7 +152,7 @@ public enum ProtocolUtils {
       BinaryTagTypes.COMPOUND, BinaryTagTypes.INT_ARRAY, BinaryTagTypes.LONG_ARRAY};
   private static final QuietDecoderException BAD_VARINT_CACHED =
       new QuietDecoderException("Bad VarInt decoded");
-  private static final int[] VAR_INT_LENGTHS = new int[65];
+  private static final int[] VAR_INT_LENGTHS = new int[33];
 
   static {
     for (int i = 0; i <= 32; ++i) {
@@ -143,6 +161,9 @@ public enum ProtocolUtils {
     VAR_INT_LENGTHS[32] = 1; // Special case for the number 0.
   }
 
+  public static final int DEFAULT_MAX_STRING_BYTES = varIntBytes(ByteBufUtil.utf8MaxBytes(DEFAULT_MAX_STRING_SIZE))
+          + ByteBufUtil.utf8MaxBytes(DEFAULT_MAX_STRING_SIZE);
+
   private static DecoderException badVarint() {
     return MinecraftDecoder.DEBUG ? new CorruptedFrameException("Bad VarInt decoded")
         : BAD_VARINT_CACHED;
@@ -234,16 +255,15 @@ public enum ProtocolUtils {
   }
 
   /**
-   * Writes the specified {@code value} as a 21-bit Minecraft VarInt to the specified {@code buf}.
+   * Directly encodes a 21-bit Minecraft VarInt, ready to be written with {@link ByteBuf#writeMedium(int)}.
    * The upper 11 bits will be discarded.
    *
-   * @param buf   the buffer to read from
-   * @param value the integer to write
+   * @param value the value to encode
+   * @return the encoded value
    */
-  public static void write21BitVarInt(ByteBuf buf, int value) {
+  public static int encode21BitVarInt(int value) {
     // See https://steinborn.me/posts/performance/how-fast-can-you-write-a-varint/
-    int w = (value & 0x7F | 0x80) << 16 | ((value >>> 7) & 0x7F | 0x80) << 8 | (value >>> 14);
-    buf.writeMedium(w);
+    return (value & 0x7F | 0x80) << 16 | ((value >>> 7) & 0x7F | 0x80) << 8 | (value >>> 14);
   }
 
   public static String readString(ByteBuf buf) {
@@ -272,12 +292,22 @@ public enum ProtocolUtils {
     checkFrame(buf.isReadable(length),
         "Trying to read a string that is too long (wanted %s, only have %s)", length,
         buf.readableBytes());
-    String str = buf.toString(buf.readerIndex(), length, StandardCharsets.UTF_8);
-    buf.skipBytes(length);
+    String str = buf.readString(length, StandardCharsets.UTF_8);
     checkFrame(str.length() <= cap, "Got a too-long string (got %s, max %s)", str.length(), cap);
     return str;
   }
 
+  /**
+   * Determines the size of the written {@code str} if encoded as a VarInt-prefixed UTF-8 string.
+   *
+   * @param str the string to write
+   * @return the encoded size
+   */
+  public static int stringSizeHint(CharSequence str) {
+    int size = ByteBufUtil.utf8Bytes(str);
+    return varIntBytes(size) + size;
+  }
+
   /**
    * Writes the specified {@code str} to the {@code buf} with a VarInt prefix.
    *
@@ -310,6 +340,16 @@ public enum ProtocolUtils {
     writeString(buf, key.asString());
   }
 
+  /**
+   * Writes the key to the buffer, dropping the "minecraft:" namespace when present.
+   *
+   * @param buf the buffer to write to
+   * @param key the key to write
+   */
+  public static void writeMinimalKey(ByteBuf buf, Key key) {
+    writeString(buf, key.asMinimalString());
+  }
+
   /**
    * Reads a standard Mojang Text namespaced:key array from the buffer.
    *
@@ -380,7 +420,10 @@ public enum ProtocolUtils {
    */
   public static int[] readIntegerArray(ByteBuf buf) {
     int len = readVarInt(buf);
-    checkArgument(len >= 0, "Got a negative-length integer array (%s)", len);
+    checkFrame(len >= 0, "Got a negative-length integer array (%s)", len);
+    checkFrame(buf.isReadable(len),
+        "Trying to read an array that is too long (wanted %s, only have %s)", len,
+        buf.readableBytes());
     int[] array = new int[len];
     for (int i = 0; i < len; i++) {
       array[i] = readVarInt(buf);
@@ -500,6 +543,10 @@ public enum ProtocolUtils {
    */
   public static String[] readStringArray(ByteBuf buf) {
     int length = readVarInt(buf);
+    checkFrame(length >= 0, "Got a negative-length array (%s)", length);
+    checkFrame(buf.isReadable(length),
+        "Trying to read an array that is too long (wanted %s, only have %s)", length,
+        buf.readableBytes());
     String[] ret = new String[length];
     for (int i = 0; i < length; i++) {
       ret[i] = readString(buf);
@@ -611,6 +658,9 @@ public enum ProtocolUtils {
 
     checkArgument(len <= FORGE_MAX_ARRAY_LENGTH,
         "Cannot receive array longer than %s (got %s bytes)", FORGE_MAX_ARRAY_LENGTH, len);
+    checkFrame(buf.isReadable(len),
+        "Trying to read an array that is too long (wanted %s, only have %s)", len,
+        buf.readableBytes());
 
     byte[] ret = new byte[len];
     buf.readBytes(ret);
@@ -775,6 +825,63 @@ public enum ProtocolUtils {
     return new IdentifiedKeyImpl(revision, key, expiry, signature);
   }
 
+  /**
+   * Reads a {@link Sound.Source} from the buffer.
+   *
+   * @param buf the buffer
+   * @param version the protocol version
+   * @return the sound source
+   */
+  public static Sound.Source readSoundSource(ByteBuf buf, ProtocolVersion version) {
+    int ordinal = readVarInt(buf);
+
+    if (version.lessThan(ProtocolVersion.MINECRAFT_1_21_5)
+        && ordinal == Sound.Source.UI.ordinal()) {
+      throw new UnsupportedOperationException("UI sound-source is only supported in 1.21.5+");
+    }
+
+    return Sound.Source.values()[ordinal];
+  }
+
+  /**
+   * Writes a {@link Sound.Source} to the buffer.
+   *
+   * @param buf the buffer
+   * @param version the protocol version
+   * @param source the sound source to write
+   */
+  public static void writeSoundSource(ByteBuf buf, ProtocolVersion version, Sound.Source source) {
+    if (version.lessThan(ProtocolVersion.MINECRAFT_1_21_5)
+        && source == Sound.Source.UI) {
+      throw new UnsupportedOperationException("UI sound-source is only supported in 1.21.5+");
+    }
+
+    writeVarInt(buf, source.ordinal());
+  }
+
+  /**
+   * Returns a pre-sized list with a max initial size of {@code Short.MAX_VALUE}.
+   *
+   * @param initialCapacity expected initial capacity
+   * @param <T> entry type
+   * @return pre-sized list
+   */
+  public static <T> List<T> newList(int initialCapacity) {
+    return new ArrayList<>(Math.min(initialCapacity, Short.MAX_VALUE));
+  }
+
+  /**
+   * Returns a pre-sized map with a max initial size of {@code Short.MAX_VALUE}.
+   *
+   * @param initialCapacity expected initial capacity
+   * @param <K> key type
+   * @param <V> value type
+   * @return pre-sized map
+   */
+  public static <K, V> Map<K, V> newMap(int initialCapacity) {
+    return new HashMap<>(Math.min(initialCapacity, Short.MAX_VALUE));
+  }
+
   /**
    * Represents the direction in which a packet flows.
    */
@@ -782,4 +889,4 @@ public enum ProtocolUtils {
     SERVERBOUND,
     CLIENTBOUND
   }
-}
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/StateRegistry.java

@@ -41,10 +41,12 @@ import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_21_2;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_21_4;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_21_5;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_21_6;
+import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_21_9;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_7_2;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_8;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_9;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_9_4;
+import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_26_1;
 import static com.velocitypowered.api.network.ProtocolVersion.MINIMUM_VERSION;
 import static com.velocitypowered.api.network.ProtocolVersion.SUPPORTED_VERSIONS;
 import static com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
@@ -58,7 +60,11 @@ import com.velocitypowered.proxy.protocol.packet.BossBarPacket;
 import com.velocitypowered.proxy.protocol.packet.BundleDelimiterPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientSettingsPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundCookieRequestPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundSoundEntityPacket;
+import com.velocitypowered.proxy.protocol.packet.ClientboundStopSoundPacket;
 import com.velocitypowered.proxy.protocol.packet.ClientboundStoreCookiePacket;
+import com.velocitypowered.proxy.protocol.packet.DialogClearPacket;
+import com.velocitypowered.proxy.protocol.packet.DialogShowPacket;
 import com.velocitypowered.proxy.protocol.packet.DisconnectPacket;
 import com.velocitypowered.proxy.protocol.packet.EncryptionRequestPacket;
 import com.velocitypowered.proxy.protocol.packet.EncryptionResponsePacket;
@@ -81,6 +87,7 @@ import com.velocitypowered.proxy.protocol.packet.ServerDataPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerLoginPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerLoginSuccessPacket;
 import com.velocitypowered.proxy.protocol.packet.ServerboundCookieResponsePacket;
+import com.velocitypowered.proxy.protocol.packet.ServerboundCustomClickActionPacket;
 import com.velocitypowered.proxy.protocol.packet.SetCompressionPacket;
 import com.velocitypowered.proxy.protocol.packet.StatusPingPacket;
 import com.velocitypowered.proxy.protocol.packet.StatusRequestPacket;
@@ -88,6 +95,7 @@ import com.velocitypowered.proxy.protocol.packet.StatusResponsePacket;
 import com.velocitypowered.proxy.protocol.packet.TabCompleteRequestPacket;
 import com.velocitypowered.proxy.protocol.packet.TabCompleteResponsePacket;
 import com.velocitypowered.proxy.protocol.packet.TransferPacket;
+import com.velocitypowered.proxy.protocol.packet.UpdateTeamsPacket;
 import com.velocitypowered.proxy.protocol.packet.UpsertPlayerInfoPacket;
 import com.velocitypowered.proxy.protocol.packet.chat.ChatAcknowledgementPacket;
 import com.velocitypowered.proxy.protocol.packet.chat.PlayerChatCompletionPacket;
@@ -101,6 +109,8 @@ import com.velocitypowered.proxy.protocol.packet.chat.session.UnsignedPlayerComm
 import com.velocitypowered.proxy.protocol.packet.config.ActiveFeaturesPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundCustomReportDetailsPacket;
 import com.velocitypowered.proxy.protocol.packet.config.ClientboundServerLinksPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductAcceptPacket;
+import com.velocitypowered.proxy.protocol.packet.config.CodeOfConductPacket;
 import com.velocitypowered.proxy.protocol.packet.config.FinishedUpdatePacket;
 import com.velocitypowered.proxy.protocol.packet.config.KnownPacksPacket;
 import com.velocitypowered.proxy.protocol.packet.config.RegistrySyncPacket;
@@ -183,6 +193,12 @@ public enum StateRegistry {
           KnownPacksPacket.class,
           KnownPacksPacket::new,
           map(0x07, MINECRAFT_1_20_5, false));
+      serverbound.register(ServerboundCustomClickActionPacket.class, ServerboundCustomClickActionPacket::new,
+          map(0x08, MINECRAFT_1_21_6, false));
+      serverbound.register(
+          CodeOfConductAcceptPacket.class,
+          () -> CodeOfConductAcceptPacket.INSTANCE,
+          map(0x09, MINECRAFT_1_21_9, false));
 
       clientbound.register(
           ClientboundCookieRequestPacket.class, ClientboundCookieRequestPacket::new,
@@ -237,6 +253,12 @@ public enum StateRegistry {
           map(0x0F, MINECRAFT_1_21, false));
       clientbound.register(ClientboundServerLinksPacket.class, ClientboundServerLinksPacket::new,
           map(0x10, MINECRAFT_1_21, false));
+      clientbound.register(DialogClearPacket.class, () -> DialogClearPacket.INSTANCE,
+          map(0x11, MINECRAFT_1_21_6, false));
+      clientbound.register(DialogShowPacket.class, () -> new DialogShowPacket(this),
+          map(0x12, MINECRAFT_1_21_6, false));
+      clientbound.register(CodeOfConductPacket.class, CodeOfConductPacket::new,
+          map(0x13, MINECRAFT_1_21_9, false));
     }
   },
   PLAY {
@@ -258,7 +280,8 @@ public enum StateRegistry {
           map(0x0A, MINECRAFT_1_20_2, false),
           map(0x0B, MINECRAFT_1_20_5, false),
           map(0x0D, MINECRAFT_1_21_2, false),
-          map(0x0E, MINECRAFT_1_21_6, false));
+          map(0x0E, MINECRAFT_1_21_6, false),
+          map(0x0F, MINECRAFT_26_1, false));
       serverbound.register(
           LegacyChatPacket.class,
           LegacyChatPacket::new,
@@ -272,7 +295,8 @@ public enum StateRegistry {
           ChatAcknowledgementPacket::new,
           map(0x03, MINECRAFT_1_19_3, false),
           map(0x04, MINECRAFT_1_21_2, false),
-          map(0x05, MINECRAFT_1_21_6, false));
+          map(0x05, MINECRAFT_1_21_6, false),
+          map(0x06, MINECRAFT_26_1, false));
       serverbound.register(KeyedPlayerCommandPacket.class, KeyedPlayerCommandPacket::new,
           map(0x03, MINECRAFT_1_19, false),
           map(0x04, MINECRAFT_1_19_1, MINECRAFT_1_19_1, false));
@@ -283,18 +307,21 @@ public enum StateRegistry {
           map(0x04, MINECRAFT_1_19_3, false),
           map(0x05, MINECRAFT_1_20_5, false),
           map(0x06, MINECRAFT_1_21_2, false),
-          map(0x07, MINECRAFT_1_21_6, false));
+          map(0x07, MINECRAFT_1_21_6, false),
+          map(0x08, MINECRAFT_26_1, false));
       serverbound.register(UnsignedPlayerCommandPacket.class, UnsignedPlayerCommandPacket::new,
           map(0x04, MINECRAFT_1_20_5, false),
           map(0x05, MINECRAFT_1_21_2, false),
-          map(0x06, MINECRAFT_1_21_6, false));
+          map(0x06, MINECRAFT_1_21_6, false),
+          map(0x07, MINECRAFT_26_1, false));
       serverbound.register(
           SessionPlayerChatPacket.class,
           SessionPlayerChatPacket::new,
           map(0x05, MINECRAFT_1_19_3, false),
           map(0x06, MINECRAFT_1_20_5, false),
           map(0x07, MINECRAFT_1_21_2, false),
-          map(0x08, MINECRAFT_1_21_6, false));
+          map(0x08, MINECRAFT_1_21_6, false),
+          map(0x09, MINECRAFT_26_1, false));
       serverbound.register(
           ClientSettingsPacket.class,
           ClientSettingsPacket::new,
@@ -310,12 +337,14 @@ public enum StateRegistry {
           map(0x09, MINECRAFT_1_20_2, false),
           map(0x0A, MINECRAFT_1_20_5, false),
           map(0x0C, MINECRAFT_1_21_2, false),
-          map(0x0D, MINECRAFT_1_21_6, false));
+          map(0x0D, MINECRAFT_1_21_6, false),
+          map(0x0E, MINECRAFT_26_1, false));
       serverbound.register(
           ServerboundCookieResponsePacket.class, ServerboundCookieResponsePacket::new,
           map(0x11, MINECRAFT_1_20_5, false),
           map(0x13, MINECRAFT_1_21_2, false),
-          map(0x14, MINECRAFT_1_21_6, false));
+          map(0x14, MINECRAFT_1_21_6, false),
+          map(0x15, MINECRAFT_26_1, false));
       serverbound.register(
           PluginMessagePacket.class,
           PluginMessagePacket::new,
@@ -334,7 +363,8 @@ public enum StateRegistry {
           map(0x10, MINECRAFT_1_20_3, false),
           map(0x12, MINECRAFT_1_20_5, false),
           map(0x14, MINECRAFT_1_21_2, false),
-          map(0x15, MINECRAFT_1_21_6, false));
+          map(0x15, MINECRAFT_1_21_6, false),
+          map(0x16, MINECRAFT_26_1, false));
       serverbound.register(
           KeepAlivePacket.class,
           KeepAlivePacket::new,
@@ -354,7 +384,8 @@ public enum StateRegistry {
           map(0x15, MINECRAFT_1_20_3, false),
           map(0x18, MINECRAFT_1_20_5, false),
           map(0x1A, MINECRAFT_1_21_2, false),
-          map(0x1B, MINECRAFT_1_21_6, false));
+          map(0x1B, MINECRAFT_1_21_6, false),
+          map(0x1C, MINECRAFT_26_1, false));
       serverbound.register(
           ResourcePackResponsePacket.class,
           ResourcePackResponsePacket::new,
@@ -372,13 +403,15 @@ public enum StateRegistry {
           map(0x2B, MINECRAFT_1_20_5, false),
           map(0x2D, MINECRAFT_1_21_2, false),
           map(0x2F, MINECRAFT_1_21_4, false),
-          map(0x30, MINECRAFT_1_21_6, false));
+          map(0x30, MINECRAFT_1_21_6, false),
+          map(0x31, MINECRAFT_26_1, false));
       serverbound.register(
           FinishedUpdatePacket.class, () -> FinishedUpdatePacket.INSTANCE,
           map(0x0B, MINECRAFT_1_20_2, false),
           map(0x0C, MINECRAFT_1_20_5, false),
           map(0x0E, MINECRAFT_1_21_2, false),
-          map(0x0F, MINECRAFT_1_21_6, false));
+          map(0x0F, MINECRAFT_1_21_6, false),
+          map(0x10, MINECRAFT_26_1, false));
 
       clientbound.register(
           BossBarPacket.class,
@@ -430,6 +463,28 @@ public enum StateRegistry {
           ClientboundCookieRequestPacket.class, ClientboundCookieRequestPacket::new,
           map(0x16, MINECRAFT_1_20_5, false),
           map(0x15, MINECRAFT_1_21_5, false));
+      clientbound.register(
+          ClientboundSoundEntityPacket.class, ClientboundSoundEntityPacket::new,
+          map(0x5D, MINECRAFT_1_19_3, true),
+          map(0x61, MINECRAFT_1_19_4, true),
+          map(0x63, MINECRAFT_1_20_2, true),
+          map(0x65, MINECRAFT_1_20_3, true),
+          map(0x67, MINECRAFT_1_20_5, true),
+          map(0x6E, MINECRAFT_1_21_2, true),
+          map(0x6D, MINECRAFT_1_21_5, true),
+          map(0x72, MINECRAFT_1_21_9, true),
+          map(0x74, MINECRAFT_26_1, true));
+      clientbound.register(
+          ClientboundStopSoundPacket.class, ClientboundStopSoundPacket::new,
+          map(0x5F, MINECRAFT_1_19_3, true),
+          map(0x63, MINECRAFT_1_19_4, true),
+          map(0x66, MINECRAFT_1_20_2, true),
+          map(0x68, MINECRAFT_1_20_3, true),
+          map(0x6A, MINECRAFT_1_20_5, true),
+          map(0x71, MINECRAFT_1_21_2, true),
+          map(0x70, MINECRAFT_1_21_5, true),
+          map(0x75, MINECRAFT_1_21_9, true),
+          map(0x77, MINECRAFT_26_1, true));
       clientbound.register(
           PluginMessagePacket.class,
           PluginMessagePacket::new,
@@ -465,7 +520,8 @@ public enum StateRegistry {
           map(0x1A, MINECRAFT_1_19_4, false),
           map(0x1B, MINECRAFT_1_20_2, false),
           map(0x1D, MINECRAFT_1_20_5, false),
-          map(0x1C, MINECRAFT_1_21_5, false));
+          map(0x1C, MINECRAFT_1_21_5, false),
+          map(0x20, MINECRAFT_1_21_9, false));
       clientbound.register(
           KeepAlivePacket.class,
           KeepAlivePacket::new,
@@ -484,7 +540,9 @@ public enum StateRegistry {
           map(0x24, MINECRAFT_1_20_2, false),
           map(0x26, MINECRAFT_1_20_5, false),
           map(0x27, MINECRAFT_1_21_2, false),
-          map(0x26, MINECRAFT_1_21_5, false));
+          map(0x26, MINECRAFT_1_21_5, false),
+          map(0x2B, MINECRAFT_1_21_9, false),
+          map(0x2C, MINECRAFT_26_1, false));
       clientbound.register(
           JoinGamePacket.class,
           JoinGamePacket::new,
@@ -503,7 +561,9 @@ public enum StateRegistry {
           map(0x29, MINECRAFT_1_20_2, false),
           map(0x2B, MINECRAFT_1_20_5, false),
           map(0x2C, MINECRAFT_1_21_2, false),
-          map(0x2B, MINECRAFT_1_21_5, false));
+          map(0x2B, MINECRAFT_1_21_5, false),
+          map(0x30, MINECRAFT_1_21_9, false),
+          map(0x31, MINECRAFT_26_1, false));
       clientbound.register(
           RespawnPacket.class,
           RespawnPacket::new,
@@ -525,14 +585,18 @@ public enum StateRegistry {
           map(0x45, MINECRAFT_1_20_3, true),
           map(0x47, MINECRAFT_1_20_5, true),
           map(0x4C, MINECRAFT_1_21_2, true),
-          map(0x4B, MINECRAFT_1_21_5, true));
+          map(0x4B, MINECRAFT_1_21_5, true),
+          map(0x50, MINECRAFT_1_21_9, true),
+          map(0x52, MINECRAFT_26_1, true));
       clientbound.register(
           RemoveResourcePackPacket.class,
           RemoveResourcePackPacket::new,
           map(0x43, MINECRAFT_1_20_3, false),
           map(0x45, MINECRAFT_1_20_5, false),
           map(0x4A, MINECRAFT_1_21_2, false),
-          map(0x49, MINECRAFT_1_21_5, false));
+          map(0x49, MINECRAFT_1_21_5, false),
+          map(0x4E, MINECRAFT_1_21_9, false),
+          map(0x50, MINECRAFT_26_1, false));
       clientbound.register(
           ResourcePackRequestPacket.class,
           ResourcePackRequestPacket::new,
@@ -554,7 +618,9 @@ public enum StateRegistry {
           map(0x44, MINECRAFT_1_20_3, false),
           map(0x46, MINECRAFT_1_20_5, false),
           map(0x4B, MINECRAFT_1_21_2, false),
-          map(0x4A, MINECRAFT_1_21_5, false));
+          map(0x4A, MINECRAFT_1_21_5, false),
+          map(0x4F, MINECRAFT_1_21_9, false),
+          map(0x51, MINECRAFT_26_1, false));
       clientbound.register(
           HeaderAndFooterPacket.class,
           HeaderAndFooterPacket::new,
@@ -577,7 +643,9 @@ public enum StateRegistry {
           map(0x6A, MINECRAFT_1_20_3, true),
           map(0x6D, MINECRAFT_1_20_5, true),
           map(0x74, MINECRAFT_1_21_2, true),
-          map(0x73, MINECRAFT_1_21_5, true));
+          map(0x73, MINECRAFT_1_21_5, true),
+          map(0x78, MINECRAFT_1_21_9, true),
+          map(0x7A, MINECRAFT_26_1, true));
       clientbound.register(
           LegacyTitlePacket.class,
           LegacyTitlePacket::new,
@@ -599,7 +667,9 @@ public enum StateRegistry {
           map(0x61, MINECRAFT_1_20_3, true),
           map(0x63, MINECRAFT_1_20_5, true),
           map(0x6A, MINECRAFT_1_21_2, true),
-          map(0x69, MINECRAFT_1_21_5, true));
+          map(0x69, MINECRAFT_1_21_5, true),
+          map(0x6E, MINECRAFT_1_21_9, true),
+          map(0x70, MINECRAFT_26_1, true));
       clientbound.register(
           TitleTextPacket.class,
           TitleTextPacket::new,
@@ -612,7 +682,9 @@ public enum StateRegistry {
           map(0x63, MINECRAFT_1_20_3, true),
           map(0x65, MINECRAFT_1_20_5, true),
           map(0x6C, MINECRAFT_1_21_2, true),
-          map(0x6B, MINECRAFT_1_21_5, true));
+          map(0x6B, MINECRAFT_1_21_5, true),
+          map(0x70, MINECRAFT_1_21_9, true),
+          map(0x72, MINECRAFT_26_1, true));
       clientbound.register(
           TitleActionbarPacket.class,
           TitleActionbarPacket::new,
@@ -625,7 +697,9 @@ public enum StateRegistry {
           map(0x4A, MINECRAFT_1_20_3, true),
           map(0x4C, MINECRAFT_1_20_5, true),
           map(0x51, MINECRAFT_1_21_2, true),
-          map(0x50, MINECRAFT_1_21_5, true));
+          map(0x50, MINECRAFT_1_21_5, true),
+          map(0x55, MINECRAFT_1_21_9, true),
+          map(0x57, MINECRAFT_26_1, true));
       clientbound.register(
           TitleTimesPacket.class,
           TitleTimesPacket::new,
@@ -638,7 +712,9 @@ public enum StateRegistry {
           map(0x64, MINECRAFT_1_20_3, true),
           map(0x66, MINECRAFT_1_20_5, true),
           map(0x6D, MINECRAFT_1_21_2, true),
-          map(0x6C, MINECRAFT_1_21_5, true));
+          map(0x6C, MINECRAFT_1_21_5, true),
+          map(0x71, MINECRAFT_1_21_9, true),
+          map(0x73, MINECRAFT_26_1, true));
       clientbound.register(
           TitleClearPacket.class,
           TitleClearPacket::new,
@@ -668,7 +744,9 @@ public enum StateRegistry {
           map(0x3B, MINECRAFT_1_20_2, false),
           map(0x3D, MINECRAFT_1_20_5, false),
           map(0x3F, MINECRAFT_1_21_2, false),
-          map(0x3E, MINECRAFT_1_21_5, false));
+          map(0x3E, MINECRAFT_1_21_5, false),
+          map(0x43, MINECRAFT_1_21_9, false),
+          map(0x45, MINECRAFT_26_1, false));
       clientbound.register(
           UpsertPlayerInfoPacket.class,
           UpsertPlayerInfoPacket::new,
@@ -677,12 +755,16 @@ public enum StateRegistry {
           map(0x3C, MINECRAFT_1_20_2, false),
           map(0x3E, MINECRAFT_1_20_5, false),
           map(0x40, MINECRAFT_1_21_2, false),
-          map(0x3F, MINECRAFT_1_21_5, false));
+          map(0x3F, MINECRAFT_1_21_5, false),
+          map(0x44, MINECRAFT_1_21_9, false),
+          map(0x46, MINECRAFT_26_1, false));
       clientbound.register(
           ClientboundStoreCookiePacket.class, ClientboundStoreCookiePacket::new,
           map(0x6B, MINECRAFT_1_20_5, false),
           map(0x72, MINECRAFT_1_21_2, false),
-          map(0x71, MINECRAFT_1_21_5, false));
+          map(0x71, MINECRAFT_1_21_5, false),
+          map(0x76, MINECRAFT_1_21_9, false),
+          map(0x78, MINECRAFT_26_1, false));
       clientbound.register(
           SystemChatPacket.class,
           SystemChatPacket::new,
@@ -694,7 +776,9 @@ public enum StateRegistry {
           map(0x69, MINECRAFT_1_20_3, true),
           map(0x6C, MINECRAFT_1_20_5, true),
           map(0x73, MINECRAFT_1_21_2, true),
-          map(0x72, MINECRAFT_1_21_5, true));
+          map(0x72, MINECRAFT_1_21_5, true),
+          map(0x77, MINECRAFT_1_21_9, true),
+          map(0x79, MINECRAFT_26_1, true));
       clientbound.register(
           PlayerChatCompletionPacket.class,
           PlayerChatCompletionPacket::new,
@@ -715,7 +799,9 @@ public enum StateRegistry {
           map(0x49, MINECRAFT_1_20_3, false),
           map(0x4B, MINECRAFT_1_20_5, false),
           map(0x50, MINECRAFT_1_21_2, false),
-          map(0x4F, MINECRAFT_1_21_5, false));
+          map(0x4F, MINECRAFT_1_21_5, false),
+          map(0x54, MINECRAFT_1_21_9, false),
+          map(0x56, MINECRAFT_26_1, false));
       clientbound.register(
           StartUpdatePacket.class,
           () -> StartUpdatePacket.INSTANCE,
@@ -723,7 +809,9 @@ public enum StateRegistry {
           map(0x67, MINECRAFT_1_20_3, false),
           map(0x69, MINECRAFT_1_20_5, false),
           map(0x70, MINECRAFT_1_21_2, false),
-          map(0x6F, MINECRAFT_1_21_5, false));
+          map(0x6F, MINECRAFT_1_21_5, false),
+          map(0x74, MINECRAFT_1_21_9, false),
+          map(0x76, MINECRAFT_26_1, false));
       clientbound.register(
           BundleDelimiterPacket.class,
           () -> BundleDelimiterPacket.INSTANCE,
@@ -732,17 +820,39 @@ public enum StateRegistry {
           TransferPacket.class,
           TransferPacket::new,
           map(0x73, MINECRAFT_1_20_5, false),
-          map(0x7A, MINECRAFT_1_21_2, false));
+          map(0x7A, MINECRAFT_1_21_2, false),
+          map(0x7F, MINECRAFT_1_21_9, false),
+          map(0x81, MINECRAFT_26_1, false));
       clientbound.register(
           ClientboundCustomReportDetailsPacket.class,
           ClientboundCustomReportDetailsPacket::new,
           map(0x7A, MINECRAFT_1_21, false),
-          map(0x81, MINECRAFT_1_21_2, false));
+          map(0x81, MINECRAFT_1_21_2, false),
+          map(0x86, MINECRAFT_1_21_9, false),
+          map(0x88, MINECRAFT_26_1, false));
       clientbound.register(
           ClientboundServerLinksPacket.class,
           ClientboundServerLinksPacket::new,
           map(0x7B, MINECRAFT_1_21, false),
-          map(0x82, MINECRAFT_1_21_2, false));
+          map(0x82, MINECRAFT_1_21_2, false),
+          map(0x87, MINECRAFT_1_21_9, false));
+      clientbound.register(UpdateTeamsPacket.class, UpdateTeamsPacket::new,
+              map(0x41, ProtocolVersion.MINECRAFT_1_9, true),
+              map(0x43, ProtocolVersion.MINECRAFT_1_12, true),
+              map(0x44, ProtocolVersion.MINECRAFT_1_12_1, true),
+              map(0x47, ProtocolVersion.MINECRAFT_1_13, true),
+              map(0x4B, ProtocolVersion.MINECRAFT_1_14, true),
+              map(0x4C, ProtocolVersion.MINECRAFT_1_15, true),
+              map(0x55, ProtocolVersion.MINECRAFT_1_17, true),
+              map(0x58, ProtocolVersion.MINECRAFT_1_19_1, true),
+              map(0x56, ProtocolVersion.MINECRAFT_1_19_3, true),
+              map(0x5A, ProtocolVersion.MINECRAFT_1_19_4, true),
+              map(0x5C, ProtocolVersion.MINECRAFT_1_20_2, true),
+              map(0x5E, ProtocolVersion.MINECRAFT_1_20_3, true),
+              map(0x60, ProtocolVersion.MINECRAFT_1_20_5, true),
+              map(0x67, ProtocolVersion.MINECRAFT_1_21_2, true)
+          map(0x87, MINECRAFT_1_21_9, false),
+          map(0x89, MINECRAFT_26_1, false));
     }
   },
   LOGIN {
@@ -771,7 +881,7 @@ public enum StateRegistry {
           map(0x01, MINECRAFT_1_7_2, false));
       clientbound.register(
           ServerLoginSuccessPacket.class, ServerLoginSuccessPacket::new,
-              map(0x02, MINECRAFT_1_7_2, false));
+          map(0x02, MINECRAFT_1_7_2, false));
       clientbound.register(
           SetCompressionPacket.class, SetCompressionPacket::new,
           map(0x03, MINECRAFT_1_8, false));

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/GameSpyQueryHandler.java

@@ -119,7 +119,7 @@ public class GameSpyQueryHandler extends SimpleChannelInboundHandler<DatagramPac
     int sessionId = queryMessage.readInt();
 
     switch (type) {
-      case QUERY_TYPE_HANDSHAKE: {
+      case QUERY_TYPE_HANDSHAKE -> {
         // Generate new challenge token and put it into the sessions cache
         int challengeToken = random.nextInt();
         sessions.put(senderAddress, challengeToken);
@@ -132,10 +132,9 @@ public class GameSpyQueryHandler extends SimpleChannelInboundHandler<DatagramPac
 
         DatagramPacket responsePacket = new DatagramPacket(queryResponse, msg.sender());
         ctx.writeAndFlush(responsePacket, ctx.voidPromise());
-        break;
       }
 
-      case QUERY_TYPE_STAT: {
+      case QUERY_TYPE_STAT -> {
         // Check if query was done with session previously generated using a handshake packet
         int challengeToken = queryMessage.readInt();
         Integer session = sessions.getIfPresent(senderAddress);
@@ -190,10 +189,10 @@ public class GameSpyQueryHandler extends SimpleChannelInboundHandler<DatagramPac
                   "Exception while writing GS4 response for query from {}", senderAddress, ex);
               return null;
             });
-        break;
       }
-      default:
-        // Invalid query type - just don't respond
+      default -> {
+          // Invalid query type - just don't respond
+      }
     }
   }
 

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressDecoder.java

@@ -33,20 +33,34 @@ import java.util.List;
  */
 public class MinecraftCompressDecoder extends MessageToMessageDecoder<ByteBuf> {
 
+  private static final int SERVERBOUND_MAXIMUM_UNCOMPRESSED_SIZE = 2 * 1024 * 1024; // 2MiB
   private static final int VANILLA_MAXIMUM_UNCOMPRESSED_SIZE = 8 * 1024 * 1024; // 8MiB
   private static final int HARD_MAXIMUM_UNCOMPRESSED_SIZE = 128 * 1024 * 1024; // 128MiB
 
-  private static final int UNCOMPRESSED_CAP =
+  private static final int CLIENTBOUND_UNCOMPRESSED_CAP =
       Boolean.getBoolean("velocity.increased-compression-cap")
           ? HARD_MAXIMUM_UNCOMPRESSED_SIZE : VANILLA_MAXIMUM_UNCOMPRESSED_SIZE;
+  private static final int SERVERBOUND_UNCOMPRESSED_CAP =
+          Boolean.getBoolean("velocity.increased-compression-cap")
+                  ? HARD_MAXIMUM_UNCOMPRESSED_SIZE : SERVERBOUND_MAXIMUM_UNCOMPRESSED_SIZE;
   private static final boolean SKIP_COMPRESSION_VALIDATION = Boolean.getBoolean("velocity.skip-uncompressed-packet-size-validation");
+  private static final double MAX_COMPRESSION_RATIO = Double.parseDouble(System.getProperty("velocity.max-compression-ratio", "64"));
+  private final ProtocolUtils.Direction direction;
 
   private int threshold;
   private final VelocityCompressor compressor;
 
-  public MinecraftCompressDecoder(int threshold, VelocityCompressor compressor) {
+  /**
+   * Creates a new {@code MinecraftCompressDecoder} with the specified compression {@code threshold}.
+   *
+   * @param threshold the threshold for compression. Packets with uncompressed size below this threshold will not be compressed.
+   * @param compressor the compressor instance to use
+   * @param direction the direction of the packets being decoded
+   */
+  public MinecraftCompressDecoder(int threshold, VelocityCompressor compressor, ProtocolUtils.Direction direction) {
     this.threshold = threshold;
     this.compressor = compressor;
+    this.direction = direction;
   }
 
   @Override
@@ -62,17 +76,29 @@ public class MinecraftCompressDecoder extends MessageToMessageDecoder<ByteBuf> {
       out.add(in.retain());
       return;
     }
+    int length = in.readableBytes();
 
     checkFrame(claimedUncompressedSize >= threshold, "Uncompressed size %s is less than"
         + " threshold %s", claimedUncompressedSize, threshold);
-    checkFrame(claimedUncompressedSize <= UNCOMPRESSED_CAP,
-        "Uncompressed size %s exceeds hard threshold of %s", claimedUncompressedSize,
-        UNCOMPRESSED_CAP);
-
+    if (direction == ProtocolUtils.Direction.CLIENTBOUND) {
+      checkFrame(claimedUncompressedSize <= CLIENTBOUND_UNCOMPRESSED_CAP,
+              "Uncompressed size %s exceeds hard threshold of %s", claimedUncompressedSize,
+              CLIENTBOUND_UNCOMPRESSED_CAP);
+    } else {
+      checkFrame(claimedUncompressedSize <= SERVERBOUND_UNCOMPRESSED_CAP,
+              "Uncompressed size %s exceeds hard threshold of %s", claimedUncompressedSize,
+              SERVERBOUND_UNCOMPRESSED_CAP);
+      double maxCompressedAllowed = length * MAX_COMPRESSION_RATIO;
+      checkFrame(claimedUncompressedSize <= maxCompressedAllowed,
+              "Uncompressed size %s exceeds ratio threshold of %s for compressed sized %s", claimedUncompressedSize,
+              maxCompressedAllowed, length);
+    }
     ByteBuf compatibleIn = ensureCompatible(ctx.alloc(), compressor, in);
     ByteBuf uncompressed = preferredBuffer(ctx.alloc(), compressor, claimedUncompressedSize);
     try {
       compressor.inflate(compatibleIn, uncompressed, claimedUncompressedSize);
+      checkFrame(uncompressed.writerIndex() == claimedUncompressedSize,
+              "Decompressed size %s does not match claimed uncompressed size %s", uncompressed.writerIndex(), claimedUncompressedSize);
       out.add(uncompressed);
     } catch (Exception e) {
       uncompressed.release();

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftCompressorAndLengthEncoder.java

@@ -46,7 +46,7 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
     if (uncompressed < threshold) {
       // Under the threshold, there is nothing to do.
       ProtocolUtils.writeVarInt(out, uncompressed + 1);
-      ProtocolUtils.writeVarInt(out, 0);
+      out.writeByte(0);
       out.writeBytes(msg);
     } else {
       handleCompressed(ctx, msg, out);
@@ -57,7 +57,7 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
       throws DataFormatException {
     int uncompressed = msg.readableBytes();
 
-    ProtocolUtils.write21BitVarInt(out, 0); // Dummy packet length
+    out.writeMedium(0); // Reserve the packet length
     ProtocolUtils.writeVarInt(out, uncompressed);
     ByteBuf compatibleIn = MoreByteBufUtils.ensureCompatible(ctx.alloc(), compressor, msg);
 
@@ -72,11 +72,8 @@ public class MinecraftCompressorAndLengthEncoder extends MessageToByteEncoder<By
       throw new DataFormatException("The server sent a very large (over 2MiB compressed) packet.");
     }
 
-    int writerIndex = out.writerIndex();
     int packetLength = out.readableBytes() - 3;
-    out.writerIndex(0);
-    ProtocolUtils.write21BitVarInt(out, packetLength); // Rewrite packet length
-    out.writerIndex(writerIndex);
+    out.setMedium(0, ProtocolUtils.encode21BitVarInt(packetLength)); // Rewrite packet length
   }
 
   @Override

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftDecoder.java

@@ -57,7 +57,11 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
   @Override
   public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
     if (msg instanceof ByteBuf buf) {
-      tryDecode(ctx, buf);
+      try {
+        tryDecode(ctx, buf);
+      } finally {
+        buf.release();
+      }
     } else {
       ctx.fireChannelRead(msg);
     }
@@ -65,7 +69,6 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
 
   private void tryDecode(ChannelHandlerContext ctx, ByteBuf buf) throws Exception {
     if (!ctx.channel().isActive() || !buf.isReadable()) {
-      buf.release();
       return;
     }
 
@@ -74,30 +77,29 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
     MinecraftPacket packet = this.registry.createPacket(packetId);
     if (packet == null) {
       buf.readerIndex(originalReaderIndex);
-      ctx.fireChannelRead(buf);
-    } else {
-      try {
-        doLengthSanityChecks(buf, packet);
-
-        try {
-          packet.decode(buf, direction, registry.version);
-        } catch (Exception e) {
-          throw handleDecodeFailure(e, packet, packetId);
-        }
-
-        if (buf.isReadable()) {
-          throw handleOverflow(packet, buf.readerIndex(), buf.writerIndex());
-        }
-        ctx.fireChannelRead(packet);
-      } finally {
-        buf.release();
+      if (this.direction == ProtocolUtils.Direction.SERVERBOUND && this.state != StateRegistry.PLAY) {
+        throw this.handleInvalidPacketId(packetId);
       }
+      ctx.fireChannelRead(buf.retain());
+    } else {
+      doLengthSanityChecks(buf, packet);
+
+      try {
+        packet.decode(buf, direction, registry.version);
+      } catch (Exception e) {
+        throw handleDecodeFailure(e, packet, packetId);
+      }
+
+      if (buf.isReadable()) {
+        throw handleOverflow(packet, buf.readerIndex(), buf.writerIndex());
+      }
+      ctx.fireChannelRead(packet);
     }
   }
 
   private void doLengthSanityChecks(ByteBuf buf, MinecraftPacket packet) throws Exception {
-    int expectedMinLen = packet.expectedMinLength(buf, direction, registry.version);
-    int expectedMaxLen = packet.expectedMaxLength(buf, direction, registry.version);
+    int expectedMinLen = packet.decodeExpectedMinLength(buf, direction, registry.version);
+    int expectedMaxLen = packet.decodeExpectedMaxLength(buf, direction, registry.version);
     if (expectedMaxLen != -1 && buf.readableBytes() > expectedMaxLen) {
       throw handleOverflow(packet, expectedMaxLen, buf.readableBytes());
     }
@@ -133,6 +135,14 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
     }
   }
 
+  private Exception handleInvalidPacketId(int packetId) {
+    if (DEBUG) {
+      return new CorruptedFrameException("Invalid packet " + getExtraConnectionDetail(packetId));
+    } else {
+      return DECODE_FAILED;
+    }
+  }
+
   private String getExtraConnectionDetail(int packetId) {
     return "Direction " + direction + " Protocol " + registry.version + " State " + state
         + " ID 0x" + Integer.toHexString(packetId);

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftEncoder.java

@@ -54,6 +54,19 @@ public class MinecraftEncoder extends MessageToByteEncoder<MinecraftPacket> {
     msg.encode(out, direction, registry.version);
   }
 
+  @Override
+  protected ByteBuf allocateBuffer(ChannelHandlerContext ctx, MinecraftPacket msg,
+      boolean preferDirect) throws Exception {
+    int hint = msg.encodeSizeHint(direction, registry.version);
+    if (hint < 0) {
+      return super.allocateBuffer(ctx, msg, preferDirect);
+    }
+
+    int packetId = this.registry.getPacketId(msg);
+    int totalHint = ProtocolUtils.varIntBytes(packetId) + hint;
+    return preferDirect ? ctx.alloc().ioBuffer(totalHint) : ctx.alloc().heapBuffer(totalHint);
+  }
+
   public void setProtocolVersion(final ProtocolVersion protocolVersion) {
     this.registry = state.getProtocolRegistry(direction, protocolVersion);
   }

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/MinecraftVarintFrameDecoder.java

@@ -20,6 +20,7 @@ package com.velocitypowered.proxy.protocol.netty;
 import static io.netty.util.ByteProcessor.FIND_NON_NUL;
 
 import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.proxy.network.limiter.PacketLimiter;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
@@ -32,6 +33,7 @@ import io.netty.handler.codec.CorruptedFrameException;
 import java.util.List;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Frames Minecraft server packets which are prefixed by a 21-bit VarInt encoding.
@@ -44,6 +46,8 @@ public class MinecraftVarintFrameDecoder extends ByteToMessageDecoder {
           + "Velocity with -Dvelocity.packet-decode-logging=true to see more.");
   private static final QuietDecoderException BAD_PACKET_LENGTH =
       new QuietDecoderException("Bad packet length");
+  private static final QuietDecoderException INVALID_PREAMBLE =
+          new QuietDecoderException("Invalid packet preamble");
   private static final QuietDecoderException VARINT_TOO_BIG =
       new QuietDecoderException("VarInt too big");
   private static final QuietDecoderException UNKNOWN_PACKET =
@@ -52,6 +56,8 @@ public class MinecraftVarintFrameDecoder extends ByteToMessageDecoder {
   private final ProtocolUtils.Direction direction;
   private final StateRegistry.PacketRegistry.ProtocolRegistry registry;
   private StateRegistry state;
+  @Nullable
+  private PacketLimiter packetLimiter;
 
   /**
    * Creates a new {@code MinecraftVarintFrameDecoder} decoding packets from the specified {@code Direction}.
@@ -74,69 +80,93 @@ public class MinecraftVarintFrameDecoder extends ByteToMessageDecoder {
     }
 
     // skip any runs of 0x00 we might find
+    int wlen = in.readableBytes();
     int packetStart = in.forEachByte(FIND_NON_NUL);
     if (packetStart == -1) {
       in.clear();
+      // Apply a more strict check in serverbound direction, we really shouldn't be seeing this many 0x00s
+      // even from the server, the only reason we even allow these is due to bugged servers
+      if (direction == ProtocolUtils.Direction.SERVERBOUND && wlen > 16) {
+        throw INVALID_PREAMBLE;
+      }
       return;
     }
     in.readerIndex(packetStart);
 
     // try to read the length of the packet
-    in.markReaderIndex();
-    int preIndex = in.readerIndex();
-    int length = readRawVarInt21(in);
-    if (preIndex == in.readerIndex()) {
-      return;
-    }
-    if (length < 0) {
-      throw BAD_PACKET_LENGTH;
-    }
-
-    if (length > 0) {
-      if (state == StateRegistry.HANDSHAKE && direction == ProtocolUtils.Direction.SERVERBOUND) {
-        StateRegistry.PacketRegistry.ProtocolRegistry registry =
-            state.getProtocolRegistry(direction, ProtocolVersion.MINIMUM_VERSION);
-
-        final int index = in.readerIndex();
-        final int packetId = readRawVarInt21(in);
-        // Index hasn't changed, we've read nothing
-        if (index == in.readerIndex()) {
-          in.resetReaderIndex();
-          return;
-        }
-        final int payloadLength = length - ProtocolUtils.varIntBytes(packetId);
-
-        MinecraftPacket packet = registry.createPacket(packetId);
-
-        // We handle every packet in this phase, if you said something we don't know, something is really wrong
-        if (packet == null) {
-          throw UNKNOWN_PACKET;
-        }
-
-        // We 'technically' have the incoming bytes of a payload here, and so, these can actually parse
-        // the packet if needed, so, we'll take advantage of the existing methods
-        int expectedMinLen = packet.expectedMinLength(in, direction, registry.version);
-        int expectedMaxLen = packet.expectedMaxLength(in, direction, registry.version);
-        if (expectedMaxLen != -1 && payloadLength > expectedMaxLen) {
-          throw handleOverflow(packet, expectedMaxLen, in.readableBytes());
-        }
-        if (payloadLength < expectedMinLen) {
-          throw handleUnderflow(packet, expectedMaxLen, in.readableBytes());
-        }
-
-
-        in.readerIndex(index);
+    try {
+      int length = readRawVarInt21(in);
+      if (packetStart == in.readerIndex()) {
+        return;
       }
+      if (length < 0) {
+        throw BAD_PACKET_LENGTH;
+      }
+
+      if (length > 0) {
+        if (state == StateRegistry.HANDSHAKE && direction == ProtocolUtils.Direction.SERVERBOUND) {
+          if (validateServerboundHandshakePacket(in, length)) {
+            in.readerIndex(packetStart);
+            return;
+          }
+        }
+      }
+
+      // note that zero-length packets are ignored
+      if (length > 0) {
+        if (in.readableBytes() < length) {
+          in.readerIndex(packetStart);
+        } else {
+          // If enabled, rate-limit serverbound payload bytes based on frame length
+          if (packetLimiter != null) {
+            if (!packetLimiter.account(length)) {
+              throw new QuietDecoderException(
+                      "Rate limit exceeded while processing packets for %s".formatted(
+                              ctx.channel().remoteAddress()));
+            }
+          }
+          out.add(in.readRetainedSlice(length));
+        }
+      }
+    } catch (Exception e) {
+      // Reset buffer to consistent state before propagating exception to prevent memory leaks
+      in.readerIndex(packetStart);
+      throw e;
+    }
+  }
+
+  private boolean validateServerboundHandshakePacket(ByteBuf in, int length) throws Exception {
+    StateRegistry.PacketRegistry.ProtocolRegistry registry =
+        state.getProtocolRegistry(direction, ProtocolVersion.MINIMUM_VERSION);
+
+    final int index = in.readerIndex();
+    final int packetId = readRawVarInt21(in);
+    // Index hasn't changed, we've read nothing
+    if (index == in.readerIndex()) {
+      return true;
+    }
+    final int payloadLength = length - ProtocolUtils.varIntBytes(packetId);
+
+    MinecraftPacket packet = registry.createPacket(packetId);
+
+    // We handle every packet in this phase, if you said something we don't know, something is really wrong
+    if (packet == null) {
+      throw UNKNOWN_PACKET;
     }
 
-    // note that zero-length packets are ignored
-    if (length > 0) {
-      if (in.readableBytes() < length) {
-        in.resetReaderIndex();
-      } else {
-        out.add(in.readRetainedSlice(length));
-      }
+    // We 'technically' have the incoming bytes of a payload here, and so, these can actually parse
+    // the packet if needed, so, we'll take advantage of the existing methods
+    int expectedMinLen = packet.decodeExpectedMinLength(in, direction, registry.version);
+    int expectedMaxLen = packet.decodeExpectedMaxLength(in, direction, registry.version);
+    if (expectedMaxLen != -1 && payloadLength > expectedMaxLen) {
+      throw handleOverflow(packet, expectedMaxLen, in.readableBytes());
     }
+    if (payloadLength < expectedMinLen) {
+      throw handleUnderflow(packet, expectedMaxLen, in.readableBytes());
+    }
+
+    in.readerIndex(index);
+    return false;
   }
 
   @Override
@@ -240,4 +270,8 @@ public class MinecraftVarintFrameDecoder extends ByteToMessageDecoder {
   public void setState(StateRegistry stateRegistry) {
     this.state = stateRegistry;
   }
+
+  public void setPacketLimiter(@Nullable PacketLimiter packetLimiter) {
+    this.packetLimiter = packetLimiter;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/netty/PlayPacketQueueInboundHandler.java

@@ -21,6 +21,9 @@ import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import com.velocitypowered.proxy.protocol.StateRegistry;
+import com.velocitypowered.proxy.util.except.QuietDecoderException;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufHolder;
 import io.netty.channel.ChannelDuplexHandler;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.util.ReferenceCountUtil;
@@ -41,8 +44,13 @@ import org.jetbrains.annotations.NotNull;
  */
 public class PlayPacketQueueInboundHandler extends ChannelDuplexHandler {
 
+  private static final int MAXIMUM_SIZE = Integer.getInteger("velocity.maximum-play-queue-size", 128 * 1024 * 1024); // 128MiB by default
+  private static final QuietDecoderException QUEUE_LIMIT_FAILED = new QuietDecoderException(
+      "Queue too big (greater than " + MAXIMUM_SIZE + " bytes)");
+
   private final StateRegistry.PacketRegistry.ProtocolRegistry registry;
   private final Queue<Object> queue = new ArrayDeque<>();
+  private int queueSize = 0;
 
   /**
    * Provides registries for client &amp; server bound packets.
@@ -64,6 +72,20 @@ public class PlayPacketQueueInboundHandler extends ChannelDuplexHandler {
       }
     }
 
+    int length = 0;
+    if (msg instanceof ByteBuf) {
+      // keep track of raw packets
+      length = ((ByteBuf) msg).readableBytes();
+    } else if (msg instanceof ByteBufHolder) {
+      // keep track of bytebufs wrapped inside packets
+      length = ((ByteBufHolder) msg).content().readableBytes();
+    }
+    if (this.queueSize + length > MAXIMUM_SIZE) {
+      ReferenceCountUtil.release(msg);
+      throw QUEUE_LIMIT_FAILED;
+    }
+    this.queueSize += length;
+
     // Otherwise, queue the packet
     this.queue.offer(msg);
   }
@@ -90,5 +112,6 @@ public class PlayPacketQueueInboundHandler extends ChannelDuplexHandler {
         ReferenceCountUtil.release(msg);
       }
     }
+    this.queueSize = 0;
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/AvailableCommandsPacket.java

@@ -25,7 +25,6 @@ import com.mojang.brigadier.builder.ArgumentBuilder;
 import com.mojang.brigadier.builder.LiteralArgumentBuilder;
 import com.mojang.brigadier.builder.RequiredArgumentBuilder;
 import com.mojang.brigadier.context.CommandContext;
-import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import com.mojang.brigadier.suggestion.SuggestionProvider;
 import com.mojang.brigadier.suggestion.Suggestions;
 import com.mojang.brigadier.suggestion.SuggestionsBuilder;
@@ -45,9 +44,9 @@ import io.netty.buffer.ByteBuf;
 import it.unimi.dsi.fastutil.objects.Object2IntLinkedOpenCustomHashMap;
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
 import java.util.ArrayDeque;
-import java.util.Arrays;
 import java.util.Deque;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Queue;
 import java.util.concurrent.CompletableFuture;
 import java.util.function.Predicate;
@@ -86,14 +85,14 @@ public class AvailableCommandsPacket implements MinecraftPacket {
   @Override
   public void decode(ByteBuf buf, Direction direction, ProtocolVersion protocolVersion) {
     int commands = ProtocolUtils.readVarInt(buf);
-    WireNode[] wireNodes = new WireNode[commands];
+    List<WireNode> wireNodes = ProtocolUtils.newList(commands);
     for (int i = 0; i < commands; i++) {
-      wireNodes[i] = deserializeNode(buf, i, protocolVersion);
+      wireNodes.add(deserializeNode(buf, i, protocolVersion));
     }
 
     // Iterate over the deserialized nodes and attempt to form a graph. We also resolve any cycles
     // that exist.
-    Queue<WireNode> nodeQueue = new ArrayDeque<>(Arrays.asList(wireNodes));
+    Queue<WireNode> nodeQueue = new ArrayDeque<>(wireNodes);
     while (!nodeQueue.isEmpty()) {
       boolean cycling = false;
 
@@ -112,7 +111,7 @@ public class AvailableCommandsPacket implements MinecraftPacket {
     }
 
     int rootIdx = ProtocolUtils.readVarInt(buf);
-    rootNode = (RootCommandNode<CommandSource>) wireNodes[rootIdx].built;
+    rootNode = (RootCommandNode<CommandSource>) wireNodes.get(rootIdx).built;
   }
 
   @Override
@@ -246,17 +245,17 @@ public class AvailableCommandsPacket implements MinecraftPacket {
       this.validated = false;
     }
 
-    void validate(WireNode[] wireNodes) {
+    void validate(List<WireNode> wireNodes) {
       // Ensure all children exist. Note that we delay checking if the node has been built yet;
       // that needs to come after this node is built.
       for (int child : children) {
-        if (child < 0 || child >= wireNodes.length) {
+        if (child < 0 || child >= wireNodes.size()) {
           throw new IllegalStateException("Node points to non-existent index " + child);
         }
       }
 
       if (redirectTo != -1) {
-        if (redirectTo < 0 || redirectTo >= wireNodes.length) {
+        if (redirectTo < 0 || redirectTo >= wireNodes.size()) {
           throw new IllegalStateException("Redirect node points to non-existent index "
               + redirectTo);
         }
@@ -265,7 +264,7 @@ public class AvailableCommandsPacket implements MinecraftPacket {
       this.validated = true;
     }
 
-    boolean toNode(WireNode[] wireNodes) {
+    boolean toNode(List<WireNode> wireNodes) {
       if (!this.validated) {
         this.validate(wireNodes);
       }
@@ -281,7 +280,7 @@ public class AvailableCommandsPacket implements MinecraftPacket {
 
           // Add any redirects
           if (redirectTo != -1) {
-            WireNode redirect = wireNodes[redirectTo];
+            WireNode redirect = wireNodes.get(redirectTo);
             if (redirect.built != null) {
               args.redirect(redirect.built);
             } else {
@@ -305,7 +304,7 @@ public class AvailableCommandsPacket implements MinecraftPacket {
       }
 
       for (int child : children) {
-        if (wireNodes[child].built == null) {
+        if (wireNodes.get(child).built == null) {
           // The child is not yet deserialized. The node can't be built now.
           return false;
         }
@@ -313,7 +312,7 @@ public class AvailableCommandsPacket implements MinecraftPacket {
 
       // Associate children with nodes
       for (int child : children) {
-        CommandNode<CommandSource> childNode = wireNodes[child].built;
+        CommandNode<CommandSource> childNode = wireNodes.get(child).built;
         if (!(childNode instanceof RootCommandNode)) {
           built.addChild(childNode);
         }
@@ -331,12 +330,10 @@ public class AvailableCommandsPacket implements MinecraftPacket {
           .add("redirectTo", redirectTo);
 
       if (args != null) {
-        if (args instanceof LiteralArgumentBuilder) {
-          helper.add("argsLabel",
-              ((LiteralArgumentBuilder<CommandSource>) args).getLiteral());
-        } else if (args instanceof RequiredArgumentBuilder) {
-          helper.add("argsName",
-              ((RequiredArgumentBuilder<CommandSource, ?>) args).getName());
+        if (args instanceof LiteralArgumentBuilder literal) {
+          helper.add("argsLabel", literal.getLiteral());
+        } else if (args instanceof RequiredArgumentBuilder required) {
+          helper.add("argsName", required.getName());
         }
       }
 
@@ -348,18 +345,20 @@ public class AvailableCommandsPacket implements MinecraftPacket {
    * A placeholder {@link SuggestionProvider} used internally to preserve the suggestion provider
    * name.
    */
-  public static class ProtocolSuggestionProvider implements SuggestionProvider<CommandSource> {
-
-    private final String name;
-
-    public ProtocolSuggestionProvider(String name) {
-      this.name = name;
-    }
+  public record ProtocolSuggestionProvider(String name) implements SuggestionProvider<CommandSource> {
 
     @Override
     public CompletableFuture<Suggestions> getSuggestions(CommandContext<CommandSource> context,
-        SuggestionsBuilder builder) throws CommandSyntaxException {
+        SuggestionsBuilder builder) {
       return builder.buildFuture();
     }
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    // This is a very complex packet to encode. Paper 1.21.10 + Velocity with Spark has a size of
+    // 30,334, but this is likely on the lower side. We'll use 128KiB as a more realistically-sized
+    // amount.
+    return 128 * 1024;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/BossBarPacket.java

@@ -207,30 +207,22 @@ public class BossBarPacket implements MinecraftPacket {
     this.uuid = ProtocolUtils.readUuid(buf);
     this.action = ProtocolUtils.readVarInt(buf);
     switch (action) {
-      case ADD:
+      case ADD -> {
         this.name = ComponentHolder.read(buf, version);
         this.percent = buf.readFloat();
         this.color = ProtocolUtils.readVarInt(buf);
         this.overlay = ProtocolUtils.readVarInt(buf);
         this.flags = buf.readUnsignedByte();
-        break;
-      case REMOVE:
-        break;
-      case UPDATE_PERCENT:
-        this.percent = buf.readFloat();
-        break;
-      case UPDATE_NAME:
-        this.name = ComponentHolder.read(buf, version);
-        break;
-      case UPDATE_STYLE:
+      }
+      case REMOVE -> {}
+      case UPDATE_PERCENT -> this.percent = buf.readFloat();
+      case UPDATE_NAME -> this.name = ComponentHolder.read(buf, version);
+      case UPDATE_STYLE -> {
         this.color = ProtocolUtils.readVarInt(buf);
         this.overlay = ProtocolUtils.readVarInt(buf);
-        break;
-      case UPDATE_PROPERTIES:
-        this.flags = buf.readUnsignedByte();
-        break;
-      default:
-        throw new UnsupportedOperationException("Unknown action " + action);
+      }
+      case UPDATE_PROPERTIES -> this.flags = buf.readUnsignedByte();
+      default -> throw new UnsupportedOperationException("Unknown action " + action);
     }
   }
 
@@ -242,36 +234,30 @@ public class BossBarPacket implements MinecraftPacket {
     ProtocolUtils.writeUuid(buf, uuid);
     ProtocolUtils.writeVarInt(buf, action);
     switch (action) {
-      case ADD:
-        if (name == null) {
-          throw new IllegalStateException("No name specified!");
-        }
-        name.write(buf);
-        buf.writeFloat(percent);
+      case ADD -> {
+          if (name == null) {
+              throw new IllegalStateException("No name specified!");
+          }
+          name.write(buf);
+          buf.writeFloat(percent);
+          ProtocolUtils.writeVarInt(buf, color);
+          ProtocolUtils.writeVarInt(buf, overlay);
+          buf.writeByte(flags);
+      }
+      case REMOVE -> {}
+      case UPDATE_PERCENT -> buf.writeFloat(percent);
+      case UPDATE_NAME -> {
+          if (name == null) {
+              throw new IllegalStateException("No name specified!");
+          }
+          name.write(buf);
+      }
+      case UPDATE_STYLE -> {
         ProtocolUtils.writeVarInt(buf, color);
         ProtocolUtils.writeVarInt(buf, overlay);
-        buf.writeByte(flags);
-        break;
-      case REMOVE:
-        break;
-      case UPDATE_PERCENT:
-        buf.writeFloat(percent);
-        break;
-      case UPDATE_NAME:
-        if (name == null) {
-          throw new IllegalStateException("No name specified!");
-        }
-        name.write(buf);
-        break;
-      case UPDATE_STYLE:
-        ProtocolUtils.writeVarInt(buf, color);
-        ProtocolUtils.writeVarInt(buf, overlay);
-        break;
-      case UPDATE_PROPERTIES:
-        buf.writeByte(flags);
-        break;
-      default:
-        throw new UnsupportedOperationException("Unknown action " + action);
+      }
+      case UPDATE_PROPERTIES -> buf.writeByte(flags);
+      default -> throw new UnsupportedOperationException("Unknown action " + action);
     }
   }
 

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ClientSettingsPacket.java

@@ -22,8 +22,8 @@ import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufUtil;
 import java.util.Objects;
-
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class ClientSettingsPacket implements MinecraftPacket {
@@ -135,7 +135,7 @@ public class ClientSettingsPacket implements MinecraftPacket {
     return "ClientSettings{" + "locale='" + locale + '\'' + ", viewDistance=" + viewDistance +
         ", chatVisibility=" + chatVisibility + ", chatColors=" + chatColors + ", skinParts=" +
         skinParts + ", mainHand=" + mainHand + ", chatFilteringEnabled=" + textFilteringEnabled +
-        ", clientListingAllowed=" + clientListingAllowed +  ", particleStatus=" + particleStatus + '}';
+        ", clientListingAllowed=" + clientListingAllowed + ", particleStatus=" + particleStatus + '}';
   }
 
   @Override
@@ -206,6 +206,16 @@ public class ClientSettingsPacket implements MinecraftPacket {
     return handler.handle(this);
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    return 1 + ByteBufUtil.utf8MaxBytes(16) + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1;
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    return 1 + 0 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1;
+  }
+
   @Override
   public boolean equals(@Nullable final Object o) {
     if (this == o) {
@@ -237,7 +247,7 @@ public class ClientSettingsPacket implements MinecraftPacket {
         difficulty,
         skinParts,
         mainHand,
-            textFilteringEnabled,
+        textFilteringEnabled,
         clientListingAllowed,
         particleStatus);
   }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ClientboundSoundEntityPacket.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.protocol.packet;
+
+import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
+import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import net.kyori.adventure.sound.Sound;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Random;
+
+public class ClientboundSoundEntityPacket implements MinecraftPacket {
+
+  private static final Random SEEDS_RANDOM = new Random();
+
+  private Sound sound;
+  private @Nullable Float fixedRange;
+  private int emitterEntityId;
+
+  public ClientboundSoundEntityPacket() {}
+
+  public ClientboundSoundEntityPacket(Sound sound, @Nullable Float fixedRange, int emitterEntityId) {
+    this.sound = sound;
+    this.fixedRange = fixedRange;
+    this.emitterEntityId = emitterEntityId;
+  }
+
+  @Override
+  public void decode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion protocolVersion) {
+    throw new UnsupportedOperationException("Decode is not implemented");
+  }
+
+  @Override
+  public void encode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion protocolVersion) {
+    ProtocolUtils.writeVarInt(buf, 0); // version-dependent, hardcoded sound ID
+
+    ProtocolUtils.writeMinimalKey(buf, sound.name());
+
+    buf.writeBoolean(fixedRange != null);
+    if (fixedRange != null)
+      buf.writeFloat(fixedRange);
+
+    ProtocolUtils.writeSoundSource(buf, protocolVersion, sound.source());
+
+    ProtocolUtils.writeVarInt(buf, emitterEntityId);
+
+    buf.writeFloat(sound.volume());
+
+    buf.writeFloat(sound.pitch());
+
+    buf.writeLong(sound.seed().orElse(SEEDS_RANDOM.nextLong()));
+  }
+
+  @Override
+  public boolean handle(MinecraftSessionHandler handler) {
+    return handler.handle(this);
+  }
+
+  public Sound getSound() {
+    return sound;
+  }
+
+  public void setSound(Sound sound) {
+    this.sound = sound;
+  }
+
+  public @Nullable Float getFixedRange() {
+    return fixedRange;
+  }
+
+  public void setFixedRange(@Nullable Float fixedRange) {
+    this.fixedRange = fixedRange;
+  }
+
+  public int getEmitterEntityId() {
+    return emitterEntityId;
+  }
+
+  public void setEmitterEntityId(int emitterEntityId) {
+    this.emitterEntityId = emitterEntityId;
+  }
+
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ClientboundStopSoundPacket.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.protocol.packet;
+
+import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
+import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import io.netty.buffer.ByteBuf;
+import net.kyori.adventure.key.Key;
+import net.kyori.adventure.sound.Sound;
+import net.kyori.adventure.sound.SoundStop;
+
+import javax.annotation.Nullable;
+
+public class ClientboundStopSoundPacket implements MinecraftPacket {
+
+  private @Nullable Sound.Source source;
+  private @Nullable Key soundName;
+
+  public ClientboundStopSoundPacket() {}
+
+  public ClientboundStopSoundPacket(SoundStop soundStop) {
+    this(soundStop.source(), soundStop.sound());
+  }
+
+  public ClientboundStopSoundPacket(@Nullable Sound.Source source, @Nullable Key soundName) {
+    this.source = source;
+    this.soundName = soundName;
+  }
+
+  @Override
+  public void decode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion protocolVersion) {
+    int flagsBitmask = buf.readByte();
+
+    if ((flagsBitmask & 1) != 0) {
+      source = ProtocolUtils.readSoundSource(buf, protocolVersion);
+    } else {
+      source = null;
+    }
+
+    if ((flagsBitmask & 2) != 0) {
+      soundName = ProtocolUtils.readKey(buf);
+    } else {
+      soundName = null;
+    }
+  }
+
+  @Override
+  public void encode(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion protocolVersion) {
+    int flagsBitmask = 0;
+    if (source != null && soundName == null) {
+      flagsBitmask |= 1;
+    } else if (soundName != null && source == null) {
+      flagsBitmask |= 2;
+    } else if (source != null /*&& sound != null*/) {
+      flagsBitmask |= 3;
+    }
+
+    buf.writeByte(flagsBitmask);
+
+    if (source != null) {
+      ProtocolUtils.writeSoundSource(buf, protocolVersion, source);
+    }
+
+    if (soundName != null) {
+      ProtocolUtils.writeMinimalKey(buf, soundName);
+    }
+  }
+
+  @Override
+  public boolean handle(MinecraftSessionHandler handler) {
+    return handler.handle(this);
+  }
+
+  @Nullable
+  public Sound.Source getSource() {
+    return source;
+  }
+
+  public void setSource(@Nullable Sound.Source source) {
+    this.source = source;
+  }
+
+  @Nullable
+  public Key getSoundName() {
+    return soundName;
+  }
+
+  public void setSoundName(@Nullable Key soundName) {
+    this.soundName = soundName;
+  }
+
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/DialogClearPacket.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2018-2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.protocol.packet;
+
+import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
+import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
+import io.netty.buffer.ByteBuf;
+
+public class DialogClearPacket implements MinecraftPacket {
+
+  public static final DialogClearPacket INSTANCE = new DialogClearPacket();
+
+  private DialogClearPacket() {
+  }
+
+  @Override
+  public void decode(ByteBuf buf, Direction direction, ProtocolVersion protocolVersion) {
+  }
+
+  @Override
+  public void encode(ByteBuf buf, Direction direction, ProtocolVersion protocolVersion) {
+  }
+
+  @Override
+  public boolean handle(MinecraftSessionHandler handler) {
+    return handler.handle(this);
+  }
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/DialogShowPacket.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2018-2025 Velocity Contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.velocitypowered.proxy.protocol.packet;
+
+import com.velocitypowered.api.network.ProtocolVersion;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
+import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
+import com.velocitypowered.proxy.protocol.StateRegistry;
+import io.netty.buffer.ByteBuf;
+import net.kyori.adventure.nbt.BinaryTag;
+import net.kyori.adventure.nbt.BinaryTagIO;
+
+public class DialogShowPacket implements MinecraftPacket {
+
+  private final StateRegistry state;
+  private int id;
+  private BinaryTag nbt;
+
+  public DialogShowPacket(final StateRegistry state) {
+    this.state = state;
+  }
+
+  @Override
+  public void decode(ByteBuf buf, Direction direction, ProtocolVersion protocolVersion) {
+    this.id = this.state == StateRegistry.CONFIG ? 0 : ProtocolUtils.readVarInt(buf);
+    if (this.id == 0) {
+      this.nbt = ProtocolUtils.readBinaryTag(buf, protocolVersion, BinaryTagIO.reader());
+    }
+  }
+
+  @Override
+  public void encode(ByteBuf buf, Direction direction, ProtocolVersion protocolVersion) {
+    if (this.state == StateRegistry.CONFIG) {
+      ProtocolUtils.writeBinaryTag(buf, protocolVersion, this.nbt);
+    } else {
+      ProtocolUtils.writeVarInt(buf, this.id);
+      if (this.id == 0) {
+        ProtocolUtils.writeBinaryTag(buf, protocolVersion, this.nbt);
+      }
+    }
+  }
+
+  @Override
+  public boolean handle(MinecraftSessionHandler handler) {
+    return handler.handle(this);
+  }
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/EncryptionResponsePacket.java

@@ -107,7 +107,7 @@ public class EncryptionResponsePacket implements MinecraftPacket {
   }
 
   @Override
-  public int expectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+  public int decodeExpectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
     // It turns out these come out to the same length, whether we're talking >=1.8 or not.
     // The length prefix always winds up being 2 bytes.
     int base = 256 + 2 + 2;
@@ -123,8 +123,8 @@ public class EncryptionResponsePacket implements MinecraftPacket {
   }
 
   @Override
-  public int expectedMinLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
-    int base = expectedMaxLength(buf, direction, version);
+  public int decodeExpectedMinLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    int base = decodeExpectedMaxLength(buf, direction, version);
     if (version.noLessThan(ProtocolVersion.MINECRAFT_1_19)) {
       // These are "optional"
       base -= 128 + 8;

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/HandshakePacket.java

@@ -24,6 +24,7 @@ import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import io.netty.buffer.ByteBuf;
 
 public class HandshakePacket implements MinecraftPacket {
@@ -108,14 +109,21 @@ public class HandshakePacket implements MinecraftPacket {
   }
 
   @Override
-  public int expectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction,
+  public int decodeExpectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction,
                                ProtocolVersion version) {
     return 7;
   }
 
   @Override
-  public int expectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
+  public int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
                                ProtocolVersion version) {
     return 9 + (MAXIMUM_HOSTNAME_LENGTH * 3);
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    // We could compute an exact size, but 4KiB ought to be enough to encode all reasonable
+    // sizes of this packet.
+    return 4 * 1024;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/KeepAlivePacket.java

@@ -64,6 +64,28 @@ public class KeepAlivePacket implements MinecraftPacket {
     }
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    if (version.noLessThan(ProtocolVersion.MINECRAFT_1_12_2)) {
+      return Long.BYTES;
+    } else if (version.noLessThan(ProtocolVersion.MINECRAFT_1_8)) {
+      return 5;
+    } else {
+      return Integer.BYTES;
+    }
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    if (version.noLessThan(ProtocolVersion.MINECRAFT_1_12_2)) {
+      return Long.BYTES;
+    } else if (version.noLessThan(ProtocolVersion.MINECRAFT_1_8)) {
+      return 1;
+    } else {
+      return Integer.BYTES;
+    }
+  }
+
   @Override
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LegacyPlayerListItemPacket.java

@@ -69,33 +69,25 @@ public class LegacyPlayerListItemPacket implements MinecraftPacket {
         Item item = new Item(ProtocolUtils.readUuid(buf));
         items.add(item);
         switch (action) {
-          case ADD_PLAYER:
+          case ADD_PLAYER -> {
             item.setName(ProtocolUtils.readString(buf));
             item.setProperties(ProtocolUtils.readProperties(buf));
             item.setGameMode(ProtocolUtils.readVarInt(buf));
             item.setLatency(ProtocolUtils.readVarInt(buf));
             item.setDisplayName(readOptionalComponent(buf, version));
-
             if (version.noLessThan(ProtocolVersion.MINECRAFT_1_19)) {
-              if (buf.readBoolean()) {
-                item.setPlayerKey(ProtocolUtils.readPlayerKey(version, buf));
-              }
+                if (buf.readBoolean()) {
+                    item.setPlayerKey(ProtocolUtils.readPlayerKey(version, buf));
+                }
             }
-            break;
-          case UPDATE_GAMEMODE:
-            item.setGameMode(ProtocolUtils.readVarInt(buf));
-            break;
-          case UPDATE_LATENCY:
-            item.setLatency(ProtocolUtils.readVarInt(buf));
-            break;
-          case UPDATE_DISPLAY_NAME:
-            item.setDisplayName(readOptionalComponent(buf, version));
-            break;
-          case REMOVE_PLAYER:
-            //Do nothing, all that is needed is the uuid
-            break;
-          default:
-            throw new UnsupportedOperationException("Unknown action " + action);
+          }
+          case UPDATE_GAMEMODE -> item.setGameMode(ProtocolUtils.readVarInt(buf));
+          case UPDATE_LATENCY -> item.setLatency(ProtocolUtils.readVarInt(buf));
+          case UPDATE_DISPLAY_NAME -> item.setDisplayName(readOptionalComponent(buf, version));
+          case REMOVE_PLAYER -> {
+              //Do nothing, all that is needed is the uuid
+          }
+          default -> throw new UnsupportedOperationException("Unknown action " + action);
         }
       }
     } else {
@@ -126,39 +118,32 @@ public class LegacyPlayerListItemPacket implements MinecraftPacket {
 
         ProtocolUtils.writeUuid(buf, uuid);
         switch (action) {
-          case ADD_PLAYER:
+          case ADD_PLAYER -> {
             ProtocolUtils.writeString(buf, item.getName());
             ProtocolUtils.writeProperties(buf, item.getProperties());
             ProtocolUtils.writeVarInt(buf, item.getGameMode());
             ProtocolUtils.writeVarInt(buf, item.getLatency());
             writeDisplayName(buf, item.getDisplayName(), version);
             if (version.noLessThan(ProtocolVersion.MINECRAFT_1_19)) {
-              if (item.getPlayerKey() != null) {
-                buf.writeBoolean(true);
-                ProtocolUtils.writePlayerKey(buf, item.getPlayerKey());
-              } else {
-                buf.writeBoolean(false);
-              }
+                if (item.getPlayerKey() != null) {
+                    buf.writeBoolean(true);
+                    ProtocolUtils.writePlayerKey(buf, item.getPlayerKey());
+                } else {
+                    buf.writeBoolean(false);
+                }
             }
-            break;
-          case UPDATE_GAMEMODE:
-            ProtocolUtils.writeVarInt(buf, item.getGameMode());
-            break;
-          case UPDATE_LATENCY:
-            ProtocolUtils.writeVarInt(buf, item.getLatency());
-            break;
-          case UPDATE_DISPLAY_NAME:
-            writeDisplayName(buf, item.getDisplayName(), version);
-            break;
-          case REMOVE_PLAYER:
+          }
+          case UPDATE_GAMEMODE -> ProtocolUtils.writeVarInt(buf, item.getGameMode());
+          case UPDATE_LATENCY -> ProtocolUtils.writeVarInt(buf, item.getLatency());
+          case UPDATE_DISPLAY_NAME -> writeDisplayName(buf, item.getDisplayName(), version);
+          case REMOVE_PLAYER -> {
             // Do nothing, all that is needed is the uuid
-            break;
-          default:
-            throw new UnsupportedOperationException("Unknown action " + action);
+          }
+          default -> throw new UnsupportedOperationException("Unknown action " + action);
         }
       }
     } else {
-      Item item = items.get(0);
+      Item item = items.getFirst();
       Component displayNameComponent = item.getDisplayName();
       if (displayNameComponent != null) {
         String displayName = LegacyComponentSerializer.legacySection()
@@ -269,7 +254,7 @@ public class LegacyPlayerListItemPacket implements MinecraftPacket {
       return this;
     }
 
-    public IdentifiedKey getPlayerKey() {
+    public @Nullable IdentifiedKey getPlayerKey() {
       return playerKey;
     }
   }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LoginAcknowledgedPacket.java

@@ -36,7 +36,7 @@ public class LoginAcknowledgedPacket implements MinecraftPacket {
   }
 
   @Override
-  public int expectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
+  public int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction,
                                ProtocolVersion version) {
     return 0;
   }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LoginPluginMessagePacket.java

@@ -21,6 +21,7 @@ import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
@@ -86,4 +87,9 @@ public class LoginPluginMessagePacket extends DeferredByteBufHolder implements M
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    return content().readableBytes();
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LoginPluginResponsePacket.java

@@ -21,6 +21,7 @@ import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
@@ -88,4 +89,9 @@ public class LoginPluginResponsePacket extends DeferredByteBufHolder implements
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    return content().readableBytes();
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/PingIdentifyPacket.java

@@ -42,6 +42,16 @@ public class PingIdentifyPacket implements MinecraftPacket {
     buf.writeInt(id);
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    return Integer.BYTES;
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, ProtocolUtils.Direction direction, ProtocolVersion version) {
+    return Integer.BYTES;
+  }
+
   @Override
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/PluginMessagePacket.java

@@ -23,6 +23,7 @@ import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import com.velocitypowered.proxy.protocol.util.DeferredByteBufHolder;
 import io.netty.buffer.ByteBuf;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
@@ -30,6 +31,9 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class PluginMessagePacket extends DeferredByteBufHolder implements MinecraftPacket {
 
+  private static final int MAX_PAYLOAD_SIZE_CLIENTBOUND = getPayloadLimit(Direction.CLIENTBOUND);
+  private static final int MAX_PAYLOAD_SIZE_SERVERBOUND = getPayloadLimit(Direction.SERVERBOUND);
+
   private @Nullable String channel;
 
   public PluginMessagePacket() {
@@ -49,6 +53,19 @@ public class PluginMessagePacket extends DeferredByteBufHolder implements Minecr
     return channel;
   }
 
+  private static int getPayloadLimit(Direction direction) {
+    if (System.getProperty("velocity.max-plugin-message-payload-size") != null) {
+      return Integer.getInteger("velocity.max-plugin-message-payload-size");
+    }
+    if (direction == Direction.SERVERBOUND) {
+      return Integer.getInteger("velocity.max-plugin-message-payload-size.serverbound", 32767);
+    } else {
+      // This is the vanilla expected limit, a payload this large feels like a nightmare given the trust
+      // we give to servers...
+      return Integer.getInteger("velocity.max-plugin-message-payload-size.clientbound", 1048576);
+    }
+  }
+
   public void setChannel(String channel) {
     this.channel = channel;
   }
@@ -99,6 +116,17 @@ public class PluginMessagePacket extends DeferredByteBufHolder implements Minecr
 
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    return ProtocolUtils.DEFAULT_MAX_STRING_BYTES +
+        (direction == Direction.CLIENTBOUND ? MAX_PAYLOAD_SIZE_CLIENTBOUND : MAX_PAYLOAD_SIZE_SERVERBOUND);
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    return 1 + 0 + 0;
+  }
+
   @Override
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);
@@ -143,4 +171,9 @@ public class PluginMessagePacket extends DeferredByteBufHolder implements Minecr
   public PluginMessagePacket touch(Object hint) {
     return (PluginMessagePacket) super.touch(hint);
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    return content().readableBytes();
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/RemovePlayerInfoPacket.java

@@ -17,7 +17,6 @@
 
 package com.velocitypowered.proxy.protocol.packet;
 
-import com.google.common.collect.Lists;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
@@ -51,7 +50,7 @@ public class RemovePlayerInfoPacket implements MinecraftPacket {
   public void decode(ByteBuf buf, ProtocolUtils.Direction direction,
       ProtocolVersion protocolVersion) {
     int length = ProtocolUtils.readVarInt(buf);
-    Collection<UUID> profilesToRemove = Lists.newArrayListWithCapacity(length);
+    Collection<UUID> profilesToRemove = ProtocolUtils.newList(length);
     for (int idx = 0; idx < length; idx++) {
       profilesToRemove.add(ProtocolUtils.readUuid(buf));
     }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ResourcePackResponsePacket.java

@@ -80,6 +80,26 @@ public class ResourcePackResponsePacket implements MinecraftPacket {
     ProtocolUtils.writeVarInt(buf, status.ordinal());
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    if (version.noLessThan(ProtocolVersion.MINECRAFT_1_20_3)) {
+      return Long.BYTES * 2 + 1;
+    } else if (version.noGreaterThan(ProtocolVersion.MINECRAFT_1_9_4)) {
+      return ProtocolUtils.DEFAULT_MAX_STRING_BYTES + 1;
+    }
+    return 1;
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    if (version.noLessThan(ProtocolVersion.MINECRAFT_1_20_3)) {
+      return Long.BYTES * 2 + 1;
+    } else if (version.noGreaterThan(ProtocolVersion.MINECRAFT_1_9_4)) {
+      return 1 + 0 + 1;
+    }
+    return 1;
+  }
+
   @Override
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);
@@ -93,4 +113,4 @@ public class ResourcePackResponsePacket implements MinecraftPacket {
             ", status=" + status +
             '}';
   }
-}
+}

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerDataPacket.java

@@ -22,6 +22,7 @@ import com.velocitypowered.api.util.Favicon;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import com.velocitypowered.proxy.protocol.packet.chat.ComponentHolder;
 import io.netty.buffer.ByteBuf;
 import org.jetbrains.annotations.Nullable;
@@ -121,4 +122,9 @@ public class ServerDataPacket implements MinecraftPacket {
   public void setSecureChatEnforced(boolean secureChatEnforced) {
     this.secureChatEnforced = secureChatEnforced;
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    return 8 * 1024;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerLoginPacket.java

@@ -150,7 +150,7 @@ public class ServerLoginPacket implements MinecraftPacket {
   }
 
   @Override
-  public int expectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+  public int decodeExpectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
     // Accommodate the rare (but likely malicious) use of UTF-8 usernames, since it is technically
     // legal on the protocol level.
     int base = 1 + (16 * 3);

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerLoginSuccessPacket.java

@@ -23,6 +23,7 @@ import com.velocitypowered.api.util.UuidUtils;
 import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
+import com.velocitypowered.proxy.protocol.ProtocolUtils.Direction;
 import com.velocitypowered.proxy.util.VelocityProperties;
 import io.netty.buffer.ByteBuf;
 import java.util.List;
@@ -132,4 +133,11 @@ public class ServerLoginSuccessPacket implements MinecraftPacket {
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);
   }
+
+  @Override
+  public int encodeSizeHint(Direction direction, ProtocolVersion version) {
+    // We could compute an exact size, but 4KiB ought to be enough to encode all reasonable
+    // sizes of this packet.
+    return 4 * 1024;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerboundCookieResponsePacket.java

@@ -65,6 +65,16 @@ public class ServerboundCookieResponsePacket implements MinecraftPacket {
     }
   }
 
+  @Override
+  public int decodeExpectedMaxLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    return ProtocolUtils.DEFAULT_MAX_STRING_BYTES + 1 + 2 + 5120;
+  }
+
+  @Override
+  public int decodeExpectedMinLength(ByteBuf buf, Direction direction, ProtocolVersion version) {
+    return 1 + 0 + 0;
+  }
+
   @Override
   public boolean handle(MinecraftSessionHandler handler) {
     return handler.handle(this);