a

core/src/main/java/art/arcane/iris/engine/platform/BukkitChunkGenerator.java

@@ -208,7 +208,9 @@ public class BukkitChunkGenerator extends ChunkGenerator implements PlatformChun
         }
         spawnChunks.complete(INMS.get().getSpawnChunkCount(world));
         BukkitPlatform.volmitPlugin().unregisterListener(this);
-        IrisWorlds.get().put(WorldIdentity.serialize(world), dimensionKey);
+        if (shouldPersistWorldRegistration(studio)) {
+            IrisWorlds.get().put(WorldIdentity.serialize(world), dimensionKey);
+        }
         return true;
     }
 
@@ -310,6 +312,10 @@ public class BukkitChunkGenerator extends ChunkGenerator implements PlatformChun
                 : IrisEngine.InitializationMode.STUDIO;
     }
 
+    static boolean shouldPersistWorldRegistration(boolean studio) {
+        return !studio;
+    }
+
     @NotNull
     @Override
     public EngineTarget getTarget() {

core/src/test/java/art/arcane/iris/engine/platform/BukkitChunkGeneratorInitializationModeTest.java

@@ -49,4 +49,10 @@ public class BukkitChunkGeneratorInitializationModeTest {
         assertFalse(BukkitChunkGenerator.shouldRunStudioHotload(true, false, true));
         assertTrue(BukkitChunkGenerator.shouldRunStudioHotload(true, false, false));
     }
+
+    @Test
+    public void transientStudioWorldsAreNotPersisted() {
+        assertFalse(BukkitChunkGenerator.shouldPersistWorldRegistration(true));
+        assertTrue(BukkitChunkGenerator.shouldPersistWorldRegistration(false));
+    }
 }