Bug 506850

Summary: kscreen-doctor will not list outputs
Product: [Plasma] KScreen Reporter: Steve Hamblett <steve.hamblett>
Component: kscreen-doctorAssignee: kscreen-bugs-null <kscreen-bugs-null>
Status: RESOLVED NOT A BUG    
Severity: normal CC: kde, nate, xaver.hugl
Priority: NOR    
Version First Reported In: 6.4.2   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Steve Hamblett 2025-07-10 08:28:14 UTC 
SUMMARY
kscreen-doctor will not list outputs

STEPS TO REPRODUCE
1.  kscreen-doctor --outputs 

OBSERVED RESULT

org.kde.kscreen: Invalid key in Output map:  "brightness"
kscreen.doctor: Invalid config.
org.kde.kscreen: Invalid key in Output map:  "brightness"


EXPECTED RESULT

List of screen outputs

SOFTWARE/OS VERSIONS
Linux/KDE Plasma:  Fedora 42
KDE Plasma Version: 6.4.2
KDE Frameworks Version:  6.15.0
Qt Version: 6.9.1

ADDITIONAL INFORMATION

Stock fully updated Fedora 42 install, kernel 6.15.4

I have 3 screens, 

1. Integrated graphics on Display Port
2. Integrated graphics on HDMI
3. NVIDIA Quadro P620 using nouveau drivers on HDMI
Comment 1 David Edmundson 2025-07-10 09:18:16 UTC 
Is this on Wayland or X11?
Comment 2 Steve Hamblett 2025-07-10 09:57:55 UTC 
(In reply to David Edmundson from comment #1)
> Is this on Wayland or X11?

Sorry forgot to mention, its Wayland.
Comment 3 Bug Janitor Service 2025-07-25 03:46:56 UTC 
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 4 Zamundaaa 2025-09-26 15:50:37 UTC 
That output suggests KScreen isn't using the Wayland backend though. Please attach the output of kscreen-doctor --info
Comment 5 Bug Janitor Service 2025-10-11 03:47:43 UTC 
🐛🧹 ⚠️ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 6 Steve Hamblett 2025-10-11 08:14:57 UTC 
Outout from kscreen-doctor --info -:

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_QScreen.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_QScreen.so
  * KSC_XRandR.so: /usr/lib64/qt6/plugins/kf6/kscreen/KSC_XRandR.so
Comment 7 Zamundaaa 2025-10-16 21:21:39 UTC 
It seems like you have QT_QPA_PLATFORM set to xcb. Please check the output of
> env | grep QT
and if it is set, try
> unset QT_QPA_PLATFORM
> kscreen-doctor -o
Comment 8 Steve Hamblett 2025-10-17 08:37:18 UTC 
(In reply to Zamundaaa from comment #7)
> It seems like you have QT_QPA_PLATFORM set to xcb. Please check the output of
> > env | grep QT
> and if it is set, try
> > unset QT_QPA_PLATFORM
> > kscreen-doctor -o

Yep, unset it, works OK now.
Comment 9 Zamundaaa 2025-10-17 13:48:41 UTC 
Okay, then please remove that env var from your system. It will cause lots of other problems in applications.