Bug 507538

Summary:	Switching primary monitor switches desktop panels
Product:	[Plasma] plasmashell	Reporter:	Dennis Schridde <heri+kde>
Component:	Panel	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED INTENTIONAL
Severity:	normal	CC:	nate, niccolo.venerandi
Priority:	NOR
Version First Reported In:	6.4.3
Target Milestone:	1.0
Platform:	NixOS
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Dennis Schridde 2025-07-27 11:09:37 UTC

SUMMARY

The screen each desktop panel is shown on appears to depend on the primary monitor setting. When moving the primary monitor flag to a different screen, the panels also get moved.

STEPS TO REPRODUCE

1. Have two screens connected to your computer
2. Set up different panels on each screen
3. "System Settings > Display & Monitor > Display Configuration > Device > Primary": set primary monitor to the other screen

OBSERVED RESULT

Observe your panels being swapped. The panel of one screen is now shown on the other monitor, and vice versa.

EXPECTED RESULT

Panels stay on the same monitor they were before. Or at least there is an option to make the panel position independent of the primary monitor flag.

SOFTWARE/OS VERSIONS

Operating System: NixOS 25.11
KDE Plasma Version: 6.4.3
KDE Frameworks Version: 6.16.0
Qt Version: 6.9.1
Kernel Version: 6.15.8 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 9 6900HS with Radeon Graphics
Memory: 32 GiB of RAM (30,6 GiB usable)
Graphics Processor 1: AMD Radeon 680M
Graphics Processor 2: AMD Radeon RX 6800S
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: ROG Zephyrus G14 GA402RK_GA402RK
System Version: 1.0

ADDITIONAL INFORMATION

I am regularly switching my primary monitor flag from the laptop screen to an external display, because that's how Valve's Proton determines where to show fullscreen games. Since in KDE Plasma this also moves my panel with the K-menu, the systray and the notification area, and some games cannot be minimized when in fullscreen mode and thus covers this panel, this makes my system inaccessible, which is very inconvenient. It would be much nicer if the panels stayed on the screen they are on, when switching the primary screen flag.

Comment 1 Nate Graham 2025-08-07 18:15:48 UTC

Yep, that's how this is expected to work.

To be more specific, the primary monitor setting doesn't affect only panels; it affects the entire desktop on the primary monitor, including any panels on it. Basically the primary monitor setting means "which physical monitor would you like your main desktop and its panels to live on?"

This is all explained in the little info tooltip next to the primary monitor checkbox.

There aren't any plans to change this; Plasma did different things in the past, and it was a huge mess. The current approach was the sustainable and maintainable outcome we settled on.

Comment 2 Dennis Schridde 2025-08-07 18:30:37 UTC

Do you know of a way to feed "primary monitor" information to applications that's different from the desktop's settings? E.g. via environment variables that are read by wayland client libraries? Or would gamescope as an intermediate compositor be my only chance to achieve this?

Comment 3 Nate Graham 2025-08-07 22:20:00 UTC

I'm not sure about that, sorry. It seems that there's a deeper UX problem here with primary screen metadata being used somewhat inappropriately.