Have recently faced the same issue on Ubuntu 18.04. It occurs rather frequently, sometimes, within ten minutes. Previously, it has never occurred. Same message is printed in the logs.
Upgrade to Ubuntu 20.04, which ships GNOME Shell 3.36.2, did not help. There is an immediate workaround, documented on the unix stack exchange/ Switching to login screen (Ctrl+Alt+F1) and back to the main (Ctrl+Alt+F2) helps: https://unix.stackexchange.com/questions/502315 /gnome-partially-stops-responding-to-mouse-keyboard -- 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/1734095 Title: Software & Updates not showing authorization popup [gnome-shell[N]: pushModal: invocation of begin_modal failed] To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-shell-legacy-bugs/+bug/1734095/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
