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Dear all,

I have a laptop with a FHD display and an external 4k monitor. When I disable
the internal laptop display and then switch workspaces, the KDE Plasma desktop
session crashes so that all I see is a black screen. I am using Wayland (to
have proper 4k handling).

I suppose the problem is not related to the external monitor being 4k, but mine
is 4k so I thought I ought to specify this. My laptop is configured to sit to
the right of my external monitor, in case this is of any importance.

Thanks for consideration.

    -quintus

Reproducible: Always

Steps to Reproduce:
1. Start a Wayland session with KDE Plasma.
2. Connect a 4k monitor to a laptop with a FHD screen,
3. In KDE's screen settings, disable the laptop display,
4. Switch workspace,
5. Crash.
Actual Results:  
The KDE Plasma session crashes, i.e. I get a black screen.

Expected Results:  
The KDE Plasma session should not crash.

It is possible to "recover" from the problem by switching to a virtual console
and executing

    $ killall plasma_session

Then I can log in again, but as soon as I switch the workspace, the crash will
happen again. At least however I can use this trick to get to the monitor
settings and re-enable the laptop display.

System information:

Operating System: openSUSE Leap 15.4
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.2
Kernel Version: 5.14.21-150400.24.18-default (64-bit)
Graphics Platform: Wayland
Processors: 8 ������ Intel������ Core��������� i5-8350U CPU @ 1.70GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel������ UHD Graphics 620