I found that the "Workspace Indicator" was causing this problem for me.
https://extensions.gnome.org/extension/21/workspace-indicator/ Clean install of 18.04 on real hardware. Xorg session. Nvidia 1050 with open source drivers. 2k resolution. Problem did NOT occur for two weeks. Installed "Workspace Indicator" and problem occurred within 24 hours. It reoccurred once or twice every subsequent 24 hours. Uninstalled "Workspace Indicator" and problem has not reoccurred for four days. The problem: gnome shell stops responding to all mouse *clicks* within OS or on gnome shell components. Mouse cursor movement is still possible. All keyboard navigation is still possible. Mouse clicks begin to work again after 5 to 10 minutes. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1181666 Title: gnome-shell randomly blocks mouse clicks from working in app windows To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-shell/+bug/1181666/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs