1.12 after update from 1.9.1 to 1.10.0 cannot open SP world, loading, shutting down internal server, crash report...

crash-report

Looks like a mod conflict

Sure, that's pretty easy conclusion with modpack this big, but we using previous versions of your mod just fine a few years now, so why now with newest version would arise mod conflict. Stacktrace is clearly from your mod, is there any lead to this? I appreciate any help or lead.

Something is messing with the Minecraft.getPlayer() in a way I didn't expect when I made changes to UMC.