1.21.5

Co-authored-by: Bjarne Koll <git@lynxplay.dev>
Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>
Co-authored-by: Lulu13022002 <41980282+Lulu13022002@users.noreply.github.com>
Co-authored-by: MiniDigger | Martin <admin@minidigger.dev>
Co-authored-by: Nassim Jahnke <nassim@njahnke.dev>
Co-authored-by: Noah van der Aa <ndvdaa@gmail.com>
Co-authored-by: Owen1212055 <23108066+Owen1212055@users.noreply.github.com>
Co-authored-by: Shane Freeder <theboyetronic@gmail.com>
Co-authored-by: Spottedleaf <Spottedleaf@users.noreply.github.com>
Co-authored-by: Tamion <70228790+notTamion@users.noreply.github.com>
Co-authored-by: Warrior <50800980+Warriorrrr@users.noreply.github.com>

paper-api/src/main/java/io/papermc/paper/InternalAPIBridge.java

@@ -1,6 +1,7 @@
 package io.papermc.paper;
 
 import net.kyori.adventure.util.Services;
+import org.bukkit.block.Biome;
 import org.bukkit.damage.DamageEffect;
 import org.jetbrains.annotations.ApiStatus;
 import org.jspecify.annotations.NullMarked;
@@ -35,5 +36,14 @@ public interface InternalAPIBridge {
      * @return the damage effect.
      */
     DamageEffect getDamageEffect(String key);
+
+    /**
+     * Constructs the legacy custom biome instance for the biome enum.
+     *
+     * @return the created biome.
+     */
+    @Deprecated(forRemoval = true, since = "1.21.5")
+    @ApiStatus.ScheduledForRemoval(inVersion = "1.22")
+    Biome constructLegacyCustomBiome();
 }