Bug 500888

Summary:	Closing laptop lid switches off external screen in dual external monitor setup on Wayland
Product:	[Plasma] kwin	Reporter:	Gábor Katona <katonag>
Component:	multi-screen	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	kde, nate, xaver.hugl
Priority:	NOR	Keywords:	multiscreen, wayland-only
Version First Reported In:	6.3.2
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:	6.3.3
Sentry Crash Report:

Description Gábor Katona 2025-03-01 11:47:08 UTC

SUMMARY
The below problem is only present on Wayland, X11 is not affected.

I have a USB-C dock with two external monitors for my laptop. The screens are configured to have only the external monitors active when docked. Connecting the laptop to the dock with open lid works fine, internal screen switches off, external screens switch on. However closing the laptop lid results in the external screens switched off. If I open the lid, everything is restored (external on, internal off). This does not happen if only one screen is connected to the dock.

Moreover, if I first close the lid with dual monitors (thus the screens switch off), then switch off one of the monitors, and after open the lid, the second monitor is still there in the screen setup; i.e. its removal is not detected.

With kscreen-doctor I can reenable the external screens while disabling the internal, however this should be done in a blind setup, as all screens are off.

STEPS TO REPRODUCE
1. Connect the laptop with open lid to a USB-C dock with two monitors connected
2. Set the screens to have only the two external active (internal display off)
3. Set "When laptop lid closed" to "do nothing" in power management setup
4. Close the lid

OBSERVED RESULT
The external screens switch off leaving the system headless

EXPECTED RESULT
The external screens should stay on.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: openSUSE Tumbleweed 20250224
KDE Plasma Version: 6.3.2
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2
Graphics Platform: Wayland

ADDITIONAL INFORMATION
See bug 486328 for a very similar resolved bug and also bug 500858 as a maybe connected one.

Comment 1 Finn 2025-03-06 08:49:32 UTC

I have the exact same issue using a USB 4 dock, except I have only a single monitor connected. Before updating my system, when closing the laptop lid my external screen would temporarily go black then resume and work standalone to my laptop. I also cannot wake the system from sleep without opening the lid, despite setting the laptop to Do Nothing when plugged in and on lid close. This issue was not occurring before a system update (unsure which package was updated).

SYSTEM / OS INFO:
OS: Aurora 41 (based on Fedora 41)
KDE Plasma: 6.3.1
KDE Frameworks: 6.11.0
Kernel: 6.12.10
Graphics platform: Wayland

Comment 2 Zamundaaa 2025-03-07 19:24:49 UTC

I can't replicate the issue on my laptop; closing the lid while the external monitor is connected just does nothing.
I also tried the same with a new output configuration, and the same thing applies.

Please attach your .config/kwinoutputconfig.json, and afterwards test if deleting that file (while not being logged in!) makes it work as expected for you too.

Comment 3 Gábor Katona 2025-03-12 20:02:41 UTC

Since last update a few days ago I do not see this bug. I did not change anything in the settings.

Comment 4 Nate Graham 2025-03-12 21:40:03 UTC

Great news!