The bug
When you put a slime egg into a spanner, it crashes your game, and when you try to get on the same world, it crashes the game until you break it.
How to reproduce
- /give @s minecraft:spawner
- /give @s minecraft:slime_spawn_egg
- Place down the spawner
- Right click it with the spawn egg
→ Game crashes
Crash report
Description: Rendering Block Entity java.lang.IllegalArgumentException: Attribute is already registered! at akr.b(SourceFile:29) at akt.b(SourceFile:30) at awf.a(SourceFile:89) at awf.a(SourceFile:341) at bib.d(SourceFile:256) at drb.a(SourceFile:20) at drb.a(SourceFile:15) at drb.a(SourceFile:10) at dqq.a(SourceFile:139) at dqq.a(SourceFile:121) at dow.a(SourceFile:606) at dos.b(SourceFile:840) at dos.a(SourceFile:747) at dos.a(SourceFile:613) at czq.e(SourceFile:941) at czq.b(SourceFile:402) at net.minecraft.client.main.Main.main(SourceFile:194) A detailed walkthrough of the error, its code path and all known details is as follows: --------------------------------------------------------------------------------------- -- Head -- Thread: Render thread Stacktrace: at akr.b(SourceFile:29) at akt.b(SourceFile:30) at awf.a(SourceFile:89) at awf.a(SourceFile:341) at bib.d(SourceFile:256) at drb.a(SourceFile:20) at drb.a(SourceFile:15) at drb.a(SourceFile:10) -- Block Entity Details -- Details: Name: minecraft:mob_spawner // bwb Block: Block{minecraft:spawner} Block location: World: (-53,63,0), Chunk: (at 11,3,0 in -4,0; contains blocks -64,0,0 to -49,255,15), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511) Block: Block{minecraft:spawner} Block location: World: (-53,63,0), Chunk: (at 11,3,0 in -4,0; contains blocks -64,0,0 to -49,255,15), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511) Stacktrace: at dqq.a(SourceFile:139) at dqq.a(SourceFile:121) at dow.a(SourceFile:606) at dos.b(SourceFile:840) at dos.a(SourceFile:747)