Bug 490522

Summary:	After locking, the screen briefly turns on before really turning off
Product:	[Plasma] plasmashell	Reporter:	Patrick Silva <bugseforuns>
Component:	Screen locking	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	REPORTED ---
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	wayland-only
Version First Reported In:	6.2.4
Target Milestone:	1.0
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Patrick Silva 2024-07-19 20:05:06 UTC

STEPS TO REPRODUCE
1. open Power Management KCM
2. open the second combobox beside "Turn off screen:" and choose "When locked: Immediately"
3. apply the change
4. lock the screen by pressing a keyboard shortcut - meta+L is the default

OBSERVED RESULT
after the last step, the screen turns off immediately, it unexpectedly turns on briefly, and then turns off

EXPECTED RESULT
the screen turns off and remains in this state until the user uses the mouse/keyboard

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.1.3
KDE Frameworks Version: 6.4.0
Qt Version: 6.7.2
Graphics Platform: Wayland

Comment 1 Nate Graham 2025-05-08 15:56:53 UTC

I can't reproduce this on current git master; can you?

Comment 2 Patrick Silva 2025-05-08 16:38:04 UTC

Yes, I can.

Operating System: Arch Linux 
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.13.0
Qt Version: 6.9.0
Graphics Platform: Wayland

Comment 3 Nate Graham 2025-05-09 16:53:09 UTC

Can you take a phone video of what it looks like to you, just to make sure I understand the issue?

Comment 4 Patrick Silva 2025-05-09 17:28:11 UTC

Sure.

https://youtu.be/TcrEqNKIY3o

Comment 5 Nate Graham 2025-05-13 16:00:41 UTC

Huh. How odd-looking.

Does it happen on X11 too, or only on Wayland?

Comment 6 Patrick Silva 2025-05-13 16:28:15 UTC

Cannot reproduce on X11.

Operating System: Arch Linux 
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.9.0
Graphics Platform: Wayland

Comment 7 Nate Graham 2025-08-13 22:38:08 UTC

Does it still happen in Plasma 6.4.4 or later?

Comment 8 Patrick Silva 2025-08-13 23:27:26 UTC

Can reproduce on Arch (Plasma 6.4.4) and neon unstable, running on different computers.