I had tried removing everything gnome-related, including the gnome extensions, but it didn't help.
The bug solved with System76 engineers patching their system76-driver. https://github.com/pop-os/system76-driver/issues/74 ** Bug watch added: github.com/pop-os/system76-driver/issues #74 https://github.com/pop-os/system76-driver/issues/74 -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-shell in Ubuntu. https://bugs.launchpad.net/bugs/1805189 Title: gnome-shell high CPU usage (~100% CPU1) in idle with external monitor To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1805189/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs