Seems a lot of OpenGL applications are just utterly broken on the RPi4, when using Ubuntu MATE 21.10. Most games for example, crash with GLXBadFBConfig. (and the stack pointed to linux-vdso.so.1(__kernel_rt_sigreturn+0x0)[0xffff8c5807dc]) I've tried everything to fix this, such as editing my /boot/firmware/config.txt file, updating to the latest bleeding edge Mesa builds via a PPA, nothing works.
It didn't always crash like this. With Ubuntu MATE 20.04, it was fine.