Ubuntu – 18.04 lock screen stopped working – screen freezes

18.04lock-screen

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When I try to lock the screen it just freezes. It is not possible to log on again. It used to work perfectly and suddenly it does not. However, I am not aware of any recent updates or similar.

I would try to reinstall the component that is responsible for locking the screen. Which one would that be?

Best Answer

You can track the bug here. Dash to Dock Gnome extension is causing it.

Upgrading packages helped for me.

Also known temporary workarounds:

  1. Ctrl+Alt+F1 after locking to repaint screen.
  2. Win+L twice to hide screen content (the dock will still be visible, though)
  3. after logging back Alt+F2, type r, enter. To reset Gnome and fix broken dock.
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