Bug 392995

Summary: Disconnecting an external monitor at the login dialog produces an empty blackness on the remaining screen
Product: [Plasma] ksmserver Reporter: Eugene Jolas <kde.org>
Component: generalAssignee: Lubos Lunak <l.lunak>
Status: RESOLVED UPSTREAM    
Severity: normal CC: kde, kde
Priority: NOR    
Version: 5.12.4   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
Latest Commit: Version Fixed In:

Description Eugene Jolas 2018-04-11 05:56:51 UTC 
Reboot with an external display attached. You should see the same login dialog on both monitors, although when tested it showed up only on the built-in monitor. Regardless, disconnect the external monitor. The remaining, internal monitor now displays a black background with just the mouse cursor remaining. Re-connecting the external monitor adds it and extends the workspace onto it such that the mouse cursor can travel onto it, but both displays are empty and black.

Conversely, attaching an external monitor if the system has been booted without one does nothing.
Comment 1 Kai Uwe Broulik 2018-04-11 06:38:44 UTC 
I think this is SDDM, not ksmserver?
Comment 2 Eugene Jolas 2018-04-11 06:42:10 UTC 
Oops, I think you're right. Guess I should file this against SDDM through Ubuntu Launchpad?
Comment 3 Christoph Feck 2018-05-09 23:25:32 UTC 
https://github.com/sddm/sddm/issues