Bug 486841

Summary:	Screen Connected to HDMI switch constantly connecting/disconnecting after login
Product:	[Plasma] KScreen	Reporter:	david
Component:	common	Assignee:	kscreen-bugs-null <kscreen-bugs-null>
Status:	NEEDSINFO WAITINGFORINFO
Severity:	normal	CC:	cwo.kde, david, xaver.hugl
Priority:	NOR
Version First Reported In:	6.0.4
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description david 2024-05-10 09:41:56 UTC

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SUMMARY
I have a 2021 Asus Flow X13 with and Nvidia GPU and a AmD APU, it has an HDMI port, when i connect an external HDMI switch, everything works fine, both screens work up until i login into my user. 

After login only the laptop screen works, and on the display settings panel the external screen is constantly connecting and disconnecting, and the external screen doesn't display anything.

If the same screen is directly connected, everything works as expected and external screen works.

STEPS TO REPRODUCE
1. Boot computer
2. Log into User
3. External screen stops working the moment I enter my password

OBSERVED RESULT
External screen doesn't display anything and is constantly connecting and disconnecting on display settings panel.

EXPECTED RESULT
Screen just works

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 40
KDE Plasma Version: 6.0.4
KDE Frameworks Version: 6.1.0
Qt Version: 6.7

ADDITIONAL INFORMATION

Comment 1 Zamundaaa 2025-10-14 16:07:32 UTC

Does this still happen in Plasma 6.4? If so, do you have any non-default settings for the display in your user?

If you delete ~/.config/kwinoutputconfig.json without being logged in to a graphical session (from the tty for example) and then log into the session, does the issue still happen?