Authentication window is painted above the lock screen
Reproduce:
- Trigger a situation that requires authentication. For example open Settings > Details > Users and click the Unlock-button
- Press Super + L to lock the screen
Observe that the authentication window is shown on top of the lock screen.
The screenshot is taken on Fedora 27 (GNOME Shell 3.26.2), the issue is also reproducible on Ubuntu 18.10 (GNOME Shell 3.28.0).
Expected behavior: Don't show the authentication box on top of the lock screen
Edited by Ghost User