F44 P6.7 No KScreen backend found

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1

Updated to KDE Plasma 6.7 and now my display config window doesn’t work. It displays the error “No KScreen backend found. Please check your KScreen installation.”
I did some googling, and ran kscreen-doctor --info, which gave me the following -

Environment: 
  * KSCREEN_BACKEND           : [not set]
  * KSCREEN_BACKEND_INPROCESS : [not set]
  * KSCREEN_LOGGING           : [not set]
Logging to                : [logging disabled]
Preferred KScreen backend : KSC_XRandR.so
Available KScreen backends:
  * KSC_Fake.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_Fake.so
  * KSC_KWayland.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_KWayland.so
  * KSC_XRandR.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_XRandR.so

I don’t know where to go now! Any help?

2

I am having the same problem. I am suspecting that the new KDE update is faulty in some way and im hoping for a quick hotfix. For me, its not even showing the login screen, it just remains black.

3

Are you guys running wayland or X11?
Can you provide any information regarding your GPU configuration?

4

wayland. Discrete 7800XT.

5

Also Wayland with a dedicated RTX3060. Doesn’t seem to be a Radeon / Nvidia related problem

6

This says you are running X11.

For wayland it will show KSC_KWayland.so

7

I set KSCREEN_BACKEND=KSC_XRandR.so in etc/environment and nothing has changed except kscreen-doctor no longer shows preferred.

Environment: 
  * KSCREEN_BACKEND           : KSC_XRandR.so
  * KSCREEN_BACKEND_INPROCESS : [not set]
  * KSCREEN_LOGGING           : [not set]
Logging to                : [logging disabled]
Preferred KScreen backend : 
Available KScreen backends:
  * KSC_Fake.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_Fake.so
  * KSC_KWayland.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_KWayland.so
  * KSC_XRandR.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_XRandR.so
8

Why are you using x11 and not wayland?

9

I don’t know :smiling_face_with_tear: I thought I was using wayland.

10

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System settings says I’m using wayland?

11

The randr backend is for x11.
The wayland backend is for wayland.

12

Figured it out. plasmazones was holding back kwin. Removed plasmazones, upgraded using Discover, reboot, everything works.

This was also causing other problems like crashing when switching desktops using the Pager widget, and various missing settings in other KCMs.

I’m surprised it wasn’t more broken than it was.

13

THANK YOU! This was exactly the issue. I’ll reach out to fuddlesworth now.