fabric 0.16.14, minecraft 1.21.5 with vullkan (a perfomance mod like sodium that rewrites the rendering engine using vulkan and not opengl). If i don't use this mod it works correctly.
Shrimpsnail commented
the resource pack uses the opengl shaders, i'll have to rewrite all the boilerplate to support that, it gives me too many moving parts to manage, maybe when i drop support for older versions