lightdm nonfunctional on active screen switch

[Pavel Melkozerov]

I have double screen configuration (2 monitors). I face such issue:

1. I lock computer by pressing (Win+L) or it lock itself by timer
2. Mouse goes out of current monitor (password input field switches to second screen)
3. Upper buttons becomes nonfunctional such as language selection button, power indicator, volume control button, logging control button.
It happens to both screens.
4. I cannot to unlock computer if language dosn't match language of password.
The hard-reset is only option possible.

I use Unity without switches to Gnome Shell.

I tried to log gnome session (it's named Ubuntu) and I couldn't reproduce the issue. If lock computer I got completely different login page. There is no switch to the password input field if I move mouse pointer to the second screen. The password input field is fixed to the main screen.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gdm3 3.28.2-0ubuntu1.3
ProcVersionSignature: Ubuntu 4.15.0-23.25-generic 4.15.18
Uname: Linux 4.15.0-23-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
CurrentDesktop: Unity:Unity7:ubuntu
Date: Tue Jul 17 11:57:02 2018
InstallationDate: Installed on 2017-04-03 (469 days ago)
InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2)
SourcePackage: gdm3
UpgradeStatus: Upgraded to bionic on 2018-05-03 (74 days ago)
mtime.conffile..etc.gdm3.custom.conf: 2017-10-23T17:14:02.815788

[Daniel van Vugt (vanvugt)]

Are you usually using Unity7 or Gnome Shell when the problem occurs?

[Pavel Melkozerov (melky)]

I use Unity without switches to Gnome Shell

[Pavel Melkozerov (melky)]

I tried to log gnome session (it's named Ubuntu) and I couldn't reproduce the issue. If lock computer I got completely different login page. There is no switch to the password input field if I move mouse pointer to the second screen. The password input field is fixed to the main screen.

[Daniel van Vugt (vanvugt)]

I see now, thanks.

The lock screen in Unity7 is actually lightdm, not gdm. That's despite the fact that you logged in originally from gdm :)