TwystedXYZ I couldn't reproduce the issue. It might be hardware-specific (maybe you have an old graphics card / driver that doesn't fully support Minecraft's OpenGL version) or it could have something to do with the server you were playing on (it has a custom resource pack and lots of other custom stuff that could cause error spam even for vanilla players).
Also your Fabric API is slightly outdated. The recommended Fabric API version for that Wurst build is 0.141.3+1.21.11, which includes some rendering-related bug fixes that 0.141.2 doesn't have. I couldn't reproduce the issue even with your older Fabric API version, but it's worth a try to see if updating might fix it for you.
