Bug 521684 - Firefox window draws over focused window when video is playing
Summary: Firefox window draws over focused window when video is playing
Status: REPORTED
Alias: None
Product: kwin
Classification: Plasma
Component: compositing (other bugs)
Version First Reported In: 6.7.0
Platform: Fedora RPMs Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2026-06-18 20:44 UTC by Jeramy Rutley
Modified: 2026-07-05 01:36 UTC (History)
1 user (show)

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


Attachments
Loss of focus while holding the Discord title bar (3.76 MB, video/mp4)
2026-06-19 01:31 UTC, Jeramy Rutley
Details
Only mouse movement. Discord is focused window (1.60 MB, video/mp4)
2026-06-19 15:14 UTC, Jeramy Rutley
Details

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Description Jeramy Rutley 2026-06-18 20:44:15 UTC
DESCRIPTION

The Firefox window is being drawn over top of the Discord window in flashes

STEPS TO REPRODUCE
1. Ensure that the taskbar/launch bar(?) is on the bottom of the screen (the default placement for KDE)
1. Open Discord (installed from Flatpak)
2. Open Firefox to a page with an embedded video, like https://kde.org/announcements/plasma/6/6.7.0/?source=plasma-welcome
3. Place the bottom of the Firefox window so that there's a small gap between it and the taskbar -- enough so that the Discord window will be able to be above the Firefox window
3. Place the Discord window so that the bottom of the window is snapped to the taskbar
4. Ensure that the focus is on Discord. Move the Discord window left and right, keeping it snapped to the taskbar

OBSERVED RESULT

The Firefox window is drawing over top of the Discord window in flashes

EXPECTED RESULT

The Discord window is always painted above the Firefox window

SOFTWARE/OS VERSIONS
Operating System: Fedora Linux 44
KDE Plasma Version: 6.7.0
KDE Frameworks Version: 6.27.0
Qt Version: 6.11.1
Kernel Version: 7.0.12-201.fc44.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × Intel® Core™ 7 240H
Memory: 16 GiB of RAM (15.3 GiB usable)
Graphics Processor 1: Intel® Graphics
Graphics Processor 2: NVIDIA GeForce RTX 5050 Laptop GPU

ADDITIONAL INFORMATION

On a Firefox tab with no video playing, everything behaves as expected. It seems to only happen with Discord so far. Clicking on the Discord title bar will not bring the window into focus -- or at least drawn on top. I took a video if that helps.
Comment 1 TraceyC 2026-06-19 00:55:01 UTC
I'm not able to reproduce this in Plasma built from git-master (Intel GPU), I'll keep it open so others can try to reproduce.
This seems very related to bug 521687

You said you took a video of this. Can you please attach it to this report? Thanks.
Comment 2 Jeramy Rutley 2026-06-19 01:31:21 UTC
Created attachment 193336 [details]
Loss of focus while holding the Discord title bar

Hopefully this didn't screw up. 

I am dragging the discord window here back and forth.
Original video is 15 seconds, but I had to cut it to the first 3 seconds for size purposes
Comment 3 Jeramy Rutley 2026-06-19 15:14:15 UTC
Created attachment 193372 [details]
Only mouse movement. Discord is focused window

Firefox has track.toggl.com open, so no video is playing. 
I am seeing the incorrect painting when I move the mouse on the Firefox window. 
 When I move the mouse around over the Discord window, the issue doesn't occur. It's intermittent, but it triggers when I move the mouse from the Discord window to the Firefox window
Once it "settles down" after a few seconds, I can freely move the mouse over the Firefox window without the issue occurring
Comment 4 Bug Janitor Service 2026-07-04 03:48:18 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.

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