Thanks @Daniel von Vugt for your comment. Meanwhile I experienced the issue again with the "Workspace Indicator" extension not being installed, so this cannot be the culprit in my case. Yet while trying to switch workspaces I briefly saw again that silly Psensor popup window "Authentication is required to update SMART data from /dev/sda". Quitting Psensor removed the blockage right away, to this is the extension to blame. Where/how best to report this apparent Psensor bug?
I had already unticked Psensor's Preferences -> Providers -> 'Enable support of udisks2' (as suggested as a workaround elsewhere), but this did not help. Now I've also unticked Preferences -> Providers -> 'Enable support of hddtemp daemon'. Since meanwhile all HDD related sensors are disabled in the Psensor preferences I am rather confident that the very annoying blockage is gone. (If not, I'll uninstall Psensor, since Gnome 3 is unable to properly deal with its strange behavior.) -- 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
