Bug 489849

Summary:	Overview doesn't show open windows on mirrored display
Product:	[Plasma] kwin	Reporter:	maelmauron
Component:	effects-overview	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	guillermo, kde-bugs, kde, leszek.lesner, maelmauron, schmchr, xaver.hugl
Priority:	NOR
Version First Reported In:	master
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=509449
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description maelmauron 2024-07-06 21:34:05 UTC

DESCRIPTION:
The Overview effect does not show any open windows on monitors mirroring the primary monitor. Although window previews do appear on the main monitor with a secondary monitor connected and configured to mirror the primary monitor, the overview always appears empty on the secondary monitor.

EXPECTED BEHAVIOR:
Window previews in the Overview effect should be correctly shown both on the primary monitor and any monitor mirroring it.

STEPS TO REPRODUCE:
- Connect a secondary monitor
- In display options, configure this monitor to mirror the primary display.
- Open one or more windows.
- Activate the Overview effect through any means / shortcut. Window previews will be shown on the primary but not on the secondary display.

ADDITIONAL INFORMATION
Tested on an AMD laptop using the amdgpu driver and a PC using an Nvidia graphics card + the nouveau driver 

SOFTWARE VERSIONS:
Tested both on Plasma 6.0 and 6.1
Qt 6.7.2-1

Comment 1 Leszek Lesner 2024-08-31 09:21:59 UTC

Can confirm. First I thought the Desktop is broken. But it appears windows are only shown per screen. Other effects that should stack windows or show them behave the same like (CTRL+F10) for example.

Comment 2 Christoph 2024-09-30 18:55:20 UTC

I can confirm this also happen with 6.1.5 and annoys me since 6.0 (because i use this to work mirrored with a projector....)

Comment 3 Christoph 2024-09-30 18:57:27 UTC

Addition: It is irellevant which monitor is set as primary. It's always the one who is "first" for the system. On a laptop the internal screen.

Comment 4 Christoph 2024-10-13 18:20:29 UTC

The problem is still present in Plasma 6.2.0

Operating System: Fedora Linux 40
KDE Plasma Version: 6.2.0
KDE Frameworks Version: 6.7.0
Qt Version: 6.7.2
Kernel Version: 6.10.12-200.fc40.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × Intel® Core™ i7-10875H CPU @ 2.30GHz
Memory: 31,0 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics
Manufacturer: LENOVO
Product Name: 82EH
System Version: Lenovo Legion C7 15IMH05

Comment 5 Christoph 2025-02-22 12:45:09 UTC

still present in 6.3.1.

Any chance we get this fixed? :-D

Comment 6 Guillermo 2025-09-07 11:24:54 UTC

*** Bug 509205 has been marked as a duplicate of this bug. ***

Comment 7 Zamundaaa 2025-09-17 18:53:06 UTC

The underlying cause is that mirroring is currently a big hack, which just makes it look like mirroring, but it's just two outputs moved and scaled to be in the same place. Once bug 481222 is fixed, there's only one output in KWin and this issue will be gone.

*** This bug has been marked as a duplicate of bug 481222 ***