Bug 514798 - Fractional scaling under Wayland copies incorrect portion of screen
Summary: Fractional scaling under Wayland copies incorrect portion of screen
Status: RESOLVED NOT A BUG
Alias: None
Product: Spectacle
Classification: Applications
Component: General (other bugs)
Version First Reported In: unspecified
Platform: CachyOS Linux
: NOR major
Target Milestone: ---
Assignee: Noah Davis
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2026-01-18 17:52 UTC by Geoffrey Mayo
Modified: 2026-01-19 19:23 UTC (History)
1 user (show)

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


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Description Geoffrey Mayo 2026-01-18 17:52:11 UTC
SUMMARY
When using Spectacle under Wayland with fractional scaling set, what is selected by the selection box and what is copied to the clipboard differs. For example, if I take a screen shot of the center of my screen, Spectacle actually copies another part of my screen to the left and up.

STEPS TO REPRODUCE
1. Press print screen
2. Select area
3. Wrong area of the screen is copied/saved to image

OBSERVED RESULT
Area copied/saved to image is actually on the top left part of screen

EXPECTED RESULT
Area copied/saved to image is exactly where the selection box was used to select the portion of the screen

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 6.17.9-2-cachyos
KDE Plasma Version: plasmashell 6.5.4
KDE Frameworks Version: (not available via kf6-config on this system)
Qt Version: qt6-base 6.10.1-2.1

ADDITIONAL INFORMATION
I searched for previous reports for Kwin, Wayland, and Spectacle. I saw bug reports regarding Wayland and fractional scaling, but none that indicated that the actual selection box in Spectacle was completely broken as I have been observing.

Info that may or may not be related in order of assumed relevancy:
Verified behavior by forcing Spectacle to use Wayland - not just assuming Wayland was being used
Monitor: Samsung ultrawide 32:9 @ 1440p
GPU: Nvidia 5070
CPU: AMD 9800x3D
Comment 1 David Redondo 2026-01-19 10:42:29 UTC
Which scale factor do you have selected? 
How far off is the selection from the result? 
Are you able to make a selection everywhere in spectacle?
Comment 2 Geoffrey Mayo 2026-01-19 19:23:37 UTC
I guess this can be closed; maybe I had a gremlin in the system?

I just spent the last 4 hours creating a python script that generates a grid-based wallpaper, setting up OBS for screen recording, + more!, and now I can't reproduce what I've been experiencing for the last couple of months. This persisted through updates, reboots, etc. The only things that have changed was setting fractional scaling back to 100% which solved my issue the other day. Now changing the setting is fine across reboots.