crash-2021-09-10_17.50.51-server.txt
^^^ Fifth Crush
crash-2021-09-10_17.56.44-server.txt
^^^ Sixth Crush

This isn't a Fabric API bug but a crash from Literally Chunk Loader - seemingly trat-mods/LiterallyChunkLoader#11.

Thanks! How did you figure it out, @Juuxel?

The error message is

Encountered undecorated Accessor method in lchunkloader.mixins.json:

Then I just scrolled down to the mod list to see what lchunkloader was, and then googled their issue tracker to see if it had been reported already.

Nice, didn't see that error message, tho.