kscreen no longer detecting disconnection of primary external monitor

[3vi1]

Since KDE/plasma updates a few weeks back, KDE seems to no longer correctly detect when my external monitor (which I set to primary, when it's connected) is disconnected. Even rebooting does not correct the problem.

The only workaround is to delete the contents of /.local/share/kscreen/ and restart the desktop.

This was working fine in earlier versions of the plasma 5 desktop and kde 5 frameworks with the same hardware.

ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: kscreen 4:5.2.1-0ubuntu1
ProcVersionSignature: Ubuntu 3.18.0-13.14-generic 3.18.5
Uname: Linux 3.18.0-13-generic x86_64
ApportVersion: 2.16.1-0ubuntu2
Architecture: amd64
CurrentDesktop: KDE
Date: Thu Feb 26 07:54:12 2015
SourcePackage: kscreen
UpgradeStatus: No upgrade log present (probably fresh install)

[3vi1 (launchpad-net-eternaldusk)]

It looks like this has improved somewhat: It's no longer necessary to delete the contents of .local/share/kscreen at least.

The problem where the system does not appropriately act upon connection/disconnection of the monitor still shows itself in several very obvious ways though:

Scenario 1:

1. Connected to external (primary) 2560x1080 monitor, put laptop to sleep.
2. Disconnect monitor.
3. Wake laptop.
4. kscreenlocker_greet is unresponsive, and trying to draw a 2560x1080 unlock screen on the laptop's 1920x1080 screen.
5. The only way to get past this is to go to a terminal and kill the locker process (which will respawn with correct screen info). The correct screen setup will be used after you unlock the respawned locker.

Scenario 2:
1. With laptop not connected to monitor, sleep system.
2. Connect to external 2560x1080 monitor.
3. Wake laptop.
4. After unlocking screen, desktop resolution is still 1920x1080, filling only the left 3/4ths of the screen.

[Sandro (sandroid)]

Chiming in to say that this affects me too.

Further detail I can add:

* This affects three systems I have installed it on, two laptops, and a desktop. All use intel graphics.
* In all cases, disconnecting a monitor crashes the session (but not all of X11, I can still see mouse)
* In all cases, using another DM I cannot recreate the failure.

It also is still happening on Kubuntu CI branch, so it hasn't (yet anyway) been fixed upstream

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Gao Shichao (xgdgsc)]

https://bugs.kde.org/show_bug.cgi?id=346535 maybe related.

[Scarlett Gately Moore (scarlettmoore)]

This bug is very old, if it is still an issue please update the bug with information from a supported release.