Describe the bug
Try to run the game on 1.21.1 neoforge 21.1.62+ and it crashes on startup.

To Reproduce
Install latest Sophisticated backpacks, core, and storage and try to run the game.

Expected behavior
Should run normally and can play a world.
Screenshots
If applicable, add screenshots to help explain your problem.

Versions
sophisticatedbackpacks-1.21-3.20.16.1111
sophisticatedcore-1.21-0.6.42.712
sophisticatedstorage-1.21-0.10.44.906
Neoforge 1.21.1 21.1.62 up to 21.1.65

crash-2024-10-03_18.17.50-client.txt

This is definitely not caused by sophisticated because it crashes when some mod tries to apply its mixins to a class. Sophisticated doesn't use any mixins at all and the only reason it is mentioned in the crash log is because that other mod's mixin error happens when sophisticated tries to register its entity renderers.

Likely issue here is that the other mod is made for a different version of mc / neoforge and you will need to figure out what that other mod is and remove / update to a version that works well with your version of neoforge / mc (depending on what code that mod is trying to change).