Everything was working swimmingly yesterday. Then, at some point, I agreed to upgrade OBS Studio. Then it didn't work - v4l2 option missing from Tools menu. So I uninstalled obs-studio, obs-plugins, v4l2loopback-dkms, deleted v4l2sink from /usr/lib/x86_64-linux-gnu. Reinstalled (apt install) and now I get the dreaded "Failed to initialize video. Your GPU may not be supported, or your graphics drivers may need to be updated." Graphics card works fine for desktop, browser, YouTube. OpenGL version 4.60. Log is short - see attached.