Bug 509102

Summary: Broken screen geometry in fullscreen applications
Product: [Plasma] kwin Reporter: Evgeny <atxnsk>
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: CLOSED INTENTIONAL    
Severity: major CC: xaver.hugl
Priority: NOR    
Version First Reported In: 6.4.4   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: result of screenshot in Spectacle

Description Evgeny 2025-09-04 11:35:44 UTC
Created attachment 184704 [details]
result of screenshot in Spectacle

SUMMARY

In fulscreen applications (like Steam, Spectacle, etc.) broken screen geometry. 


STEPS TO REPRODUCE

Use verions KDE/Frameworks/Wt of my and run game from Steam or Spectacle)

OBSERVED RESULT

Broken screen geometry. My desktop screen 2560x1080, but application implenet this as 512x1080 screen in fullscreen mode (see screenshot in attachment).

EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch Linux 
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.2

ADDITIONAL INFORMATION
Kernel 6.16
Wayland
AMD 6800XT (mesa driver)
Comment 1 Evgeny 2025-09-04 11:45:38 UTC
Not sure about Spectacle, but other fullscreen applicaton uses XWayland. With "native" application (like Dolphin) all ok. 
And popum menu in application uses XWayland is sticky on left top corner.
Comment 2 Evgeny 2025-09-04 11:49:59 UTC
But not sure. In Browser (Chrome) in X11 or Walynd mode popum menu anything is sticky on left top corner of window.
Comment 3 Zamundaaa 2025-09-05 12:08:25 UTC
Scaling of X11 applications unfortunately requires messing with resolutions - either of all displays with less than the maximum scale, or of all displays with more than 100% scale.
If you want a different tradeoff, you can change the "Legacy applications (x11)" option in the display settings.
Comment 4 Evgeny 2025-09-08 11:09:36 UTC
(In reply to Zamundaaa from comment #3)
> Scaling of X11 applications unfortunately requires messing with resolutions
> - either of all displays with less than the maximum scale, or of all
> displays with more than 100% scale.
> If you want a different tradeoff, you can change the "Legacy applications
> (x11)" option in the display settings.

Yes, I'm change setting for scaling of X11 applications in KDE Plasma system settings and this solved my problem. Thanks!