Problems with locking the screen (and gnome-shell then crashing) lately have mostly been bug 1877774, which you don't seem to have the fix for... To get the fix please try:
sudo apt update sudo apt full-upgrade Reboot and then verify your gnome-shell package is at least version 3.36.3. ** Package changed: xorg (Ubuntu) => gnome-shell (Ubuntu) ** Changed in: gnome-shell (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1886672 Title: Multiple screen display issues To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1886672/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs