https://gist.github.com/mxnmnm/2eff660af666af6cce487720d271453c
Whenever I hold an item with a 3d model such as a gravity gun or flame thrower from mekanism they are invisible starting with forge version 14.23.5.2781 and beyond. The item is invisible in my inventory, JEI, and in my hand. The items still function but them not being rendered can be really distracting especially when you think your inventory has an empty slot but it's really full with one of those items. I checked the forge changelog and I found this in forge version 14.23.5.2781
mezz: Implement rendering for item models with emissive quads (#5047)
so I'm guessing that has a lot to do with it. I'm not sure what else I should do but hopefully this can be fixed and if I need to give more information please let me know.