Bug 510614 - Dolphin window slightly undersized and gradually shrinking with fractional scaling (150%) on X11
Summary: Dolphin window slightly undersized and gradually shrinking with fractional sc...
Status: REPORTED
Alias: None
Product: dolphin
Classification: Applications
Component: general (other bugs)
Version First Reported In: 25.08.1
Platform: Manjaro Linux
: NOR normal
Target Milestone: ---
Assignee: Dolphin Bug Assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2025-10-14 20:14 UTC by Oleksii Zolotarevskyi
Modified: 2025-10-15 20:21 UTC (History)
1 user (show)

See Also:
Latest Commit:
Version Fixed/Implemented In:
Sentry Crash Report:


Attachments
Dolphin window opens undersized (3.78 MB, video/x-matroska)
2025-10-14 20:14 UTC, Oleksii Zolotarevskyi
Details
Dolphin window gradually shrinks (3.88 MB, video/mkv)
2025-10-14 20:16 UTC, Oleksii Zolotarevskyi
Details

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Description Oleksii Zolotarevskyi 2025-10-14 20:14:14 UTC
Created attachment 185776 [details]
Dolphin window opens undersized

SUMMARY

When opening Dolphin in a maximized window, the right and bottom edges do not fully reach the screen borders, leaving thin visible lines of the background application (see the first screen recording).

Additionally, when navigating through certain directories, the Dolphin window gradually shrinks by a few pixels at the bottom with each directory change (see the second screen recording).

This issue occurs only on X11 when the global display scaling is set to 150%. It does not occur at 100% scaling.  
It appears to be related to an incorrect window size calculation that accumulates over time when fractional scaling is enabled.

STEPS TO REPRODUCE
1. Set the display’s global scale to 150%
2. Open Dolphin
3. Browse through multiple directories (e.g. those shown in the video)

OBSERVED RESULT
- The maximized window does not completely fill the screen.
- The window height gradually decreases with each directory change.

EXPECTED RESULT
- The maximized window should fully occupy the screen.
- The window size should remain consistent when navigating between directories.

SOFTWARE/OS VERSIONS
- Linux/KDE Plasma: Manjaro Stable
- KDE Plasma Version: 6.3.6
- KDE Frameworks Version: 6.18.0
- Qt Version: 6.9.2

ADDITIONAL INFORMATION
- Graphics Platform: X11
- Graphics Processor: Nvidia GeForce RTX 2070 with Max-Q
- Nvidia Driver Version: 580.82.09
Comment 1 Oleksii Zolotarevskyi 2025-10-14 20:16:13 UTC
Created attachment 185777 [details]
Dolphin window gradually shrinks
Comment 2 Oleksii Zolotarevskyi 2025-10-15 20:21:12 UTC
UPDATE: I found a workaround by setting the global scaling to 143,75% instead of 150%. In such case, Dolphin window scales correctly and doesn't shrink.