Bug 472832

Summary: Panels on scaled displays with different resolutions cause gaps next to maximized windows
Product: [Plasma] kwin Reporter: johnnyjayjay02
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: nate
Priority: NOR Keywords: multiscreen
Version: 5.27.6   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=414522
https://bugs.kde.org/show_bug.cgi?id=459373
Latest Commit: Version Fixed In: 6.0
Sentry Crash Report:
Attachments: Visible gap between window and panel

Description johnnyjayjay02 2023-07-31 09:54:35 UTC 
Created attachment 160641 [details]
Visible gap between window and panel

SUMMARY
***
NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols.
See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
***
I have a 2-monitor setup: One is WQHD, the other FHD. I have applied 130% scaling to the higher resolution display so that sizes are about equal on both displays. This works fine until I add a default panel to the lower resolution screen. Then, my WQHD display cannot maximise windows properly anymore. Instead, a gap at the bottom is created.
This gap increases in size with the scaling factor used. But it is only present if there is a panel on the other display.

STEPS TO REPRODUCE
1. Have 2 different displays with different resolutions (WQHD, FHD)
2. Scale the bigger one to a value over 100%
3. Add default panels to both displays
4. Maximise a window on the WQHD display.

OBSERVED RESULT
Gaps between "maximised" windows and the panel.

EXPECTED RESULT
Windows reach all the way to the panel.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 38
KDE Plasma Version: Plasma 5.27.6
KDE Frameworks Version: 5.108.0
Qt Version: 5.15.10

ADDITIONAL INFORMATION
Not sure if I filed this under the correct category or not, feel free to move this somewhere else if not appropriate.
Comment 1 Nate Graham 2023-09-07 19:41:36 UTC 
Are you on X11? If so, the issue is most likely Bug 414522.

If you're on Wayland, does the issue only happen with XWayland-using apps, rather than native-Wayland apps? If so then the issue is most likely Bug 459373.
Comment 2 johnnyjayjay02 2023-09-07 19:46:21 UTC 
(In reply to Nate Graham from comment #1)
> Are you on X11? If so, the issue is most likely Bug 414522.
> 
> If you're on Wayland, does the issue only happen with XWayland-using apps,
> rather than native-Wayland apps? If so then the issue is most likely Bug
> 459373.

I am on Wayland (sorry that wasn't clear) and the issue happens regardless of whether I'm displaying a native or an XWayland app.
Comment 3 Nate Graham 2023-09-08 17:52:59 UTC 
Ok, thanks. Perhaps it's something else.

However I cannot reproduce the issue in Plasma 6, and there have been a *lot* of Wayland, scaling, and window maximization changes there. So let's call it fixed in Plasma 6! But feel free to re-open this if you still encounter the issue in Plasma 6 once installing or upgrading to it next February.
Comment 4 johnnyjayjay02 2023-09-11 07:31:14 UTC 
Fair enough  - I suppose I will reopen this when Fedora updates to Plasma 6 and the issue persists.
Comment 5 Nate Graham 2023-09-11 17:03:20 UTC 
You can also try again in the upcoming Plasma 5.27.8 as this version also has changes related to the issue in question that might have fixed it.