I think this might have been caused by the Pop OS! PPA (ppa:system76/pop). I think I must have installed it months ago for some icon set without realising that it loads a ton of other stuff. Its latest iteration of g-c-c segfaults, which is how I realised what was going on. Purging the PPA and using g-c-c 1:3.34.0.1-1ubuntu2, I can now see all the resolutions again.
** Changed in: mutter (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1842882 Title: gnome-control-center no longer shows all the xrandr resolutions To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1842882/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs