Bug 509502

Summary:	Screen brightness level is very reduced after unlocking screen
Product:	[Plasma] plasmashell	Reporter:	Vartan <forums.basil562>
Component:	Power management & brightness	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal	CC:	kdedev, nate
Priority:	NOR
Version First Reported In:	6.4.4
Target Milestone:	1.0
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Vartan 2025-09-14 22:41:45 UTC

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SUMMARY

After typing password to unlock the screen, the screen's brightness level is very much reduced from its level prior to the screen having been locked. 

STEPS TO REPRODUCE
1.  Lock screen either manually or by timeout 
2.  Move mouse or hit any keyboard key to display the unlock prompt display
3.  Type password to unlock screen 

OBSERVED RESULT

The display brightness level is about half (or less) of its level prior to screen locking. 

EXPECTED RESULT

The screen brightness remains precisely the same as it was prior to the screen locking.

SOFTWARE/OS VERSIONS

Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.4
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.1
Kernel Version: 6.16.3-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 7840HS w/ Radeon 780M Graphics
Memory: 32 GiB of RAM (27.1 GiB usable)
Graphics Processor: AMD Radeon 780M Graphics

ADDITIONAL INFORMATION

Comment 1 Vartan 2025-09-17 16:41:43 UTC

Additional information....

I have experienced the problem in two different scenarios.

Scenario 1:
I type my password in the text box on the lock screen display.  Upon unlocking the screen, the display brightness is reduced.

Scenario 2:
The screen dims after a period of inactivity (keyboard, mouse, etc) given by:
System Settings -> Power Management -> Dim automatically  

If I move my mouse or type a keystroke within the period given by 
System Settings -> Power Management -> Dim automatically

the screen display returns to its 'normal' brightness level.

However, sometimes, after moving the mouse or typing a keystroke, the display does not return to its normal brightness level; it remains at the dimmed level.

It seems that there is a race condition realated to both of these scenarios.

Comment 2 TraceyC 2025-10-01 17:16:06 UTC

Thanks for the bug report. This looks to be the same as bug 504441, so I'll merge this in with that one. Thanks.

*** This bug has been marked as a duplicate of bug 504441 ***