Bug 507718

Summary:	Text suggestion on GTK apps in kwin-wayland appear on the wrong monitor.
Product:	[Plasma] kwin	Reporter:	Greeniac <quarro>
Component:	general	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DOWNSTREAM
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	multiscreen
Version First Reported In:	6.4.3
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Example of the bug in GIMP (launched in wayland mode) Example of the bug in LibreOffice (also in wayland)

Description Greeniac 2025-08-01 05:01:14 UTC

SUMMARY
In most (if not all) non libadwata GTK apps (like: GIMP, LibreOffice and Virt Manager) have text suggestion for fonts or files, but when using multiple monitors, sometimes the suggestion box will appear on a diffrent monitor than the one that has the application, and that happens in both Flatpak and system package apps, and only wayland apps, so when launching in X11 mode, the issue does not happen.

STEPS TO REPRODUCE (Example: GIMP)
1.  Connect multiple monitors.
2.  Launch GIMP in Wayland mode.
3.  Make a text box and click on the font option.
4. Search for a specific font.

OBSERVED RESULT
Font suggestions sometimes appear on a different monitor.

EXPECTED RESULT
Font suggestions should appear on the same monitor.

SOFTWARE/OS VERSIONS

ADDITIONAL INFORMATION

Comment 1 Greeniac 2025-08-01 05:05:02 UTC

Created attachment 183695 [details]
Example of the bug in GIMP (launched in wayland mode)

As you can see, GIMP is on the left monitor but the text suggestion appears on the other.

Comment 2 Greeniac 2025-08-01 05:31:06 UTC

Info about my machine:

Monitors:

I have 3 monitors that are layed out as such:
[2880x1620 @60Hz] [2560x1440 @144Hz] [1920x1080 @60Hz]

All of them are set at 100% scalling, and in the photo I attatched, GIMP was in center monitor and the suggestions appeared on the left monitor.

But if I put GIMP on the left monitor, or if i make it floating and only a tiny part of GIMP is on the left monitor, the suggestions appear correctly.

And putting it on the right monitor makes the suggestions not appear at all, because it will try draw them outside the right monitor, I know this because moving GIMP slightly to the left makes the suggestion box visible on the edge, so it's clear that it was out of bounds.

I also uploaded a video showcasing all of these three cases (uploaded it to youtube because of the 4000kb attachment limit here)
https://youtu.be/sD7PyI7rvko

Software and hardware info:

Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.3
KDE Frameworks Version: 6.16.0
Qt Version: 6.9.1
Kernel Version: 6.15.8-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i5-7600K CPU @ 3.80GHz
Memory: 24 GiB of RAM (23.4 GiB usable)
Graphics Processor: AMD Radeon Pro 580X
Manufacturer: Apple Inc.
Product Name: iMac18,3
System Version: 1.0

Comment 3 Greeniac 2025-08-01 05:31:35 UTC

Created attachment 183696 [details]
Example of the bug in LibreOffice (also in wayland)

Comment 4 Greeniac 2025-08-02 10:04:54 UTC

Just tested GIMP in Fedora Workstation (GNOME 48), the issue is there also, so it's probably not a Plasma/Kwin bug, but maybe it's possible for Kwin to implement a fix in their end.

Comment 5 Nate Graham 2025-09-23 21:52:28 UTC

Indeed, this is an app or GTK toolkit bug.