Bug 414502

Summary: (Un)plugging the AC adapter while screen is off always results in 100% brightness
Product: [Plasma] plasmashell Reporter: cantabile <cantabile.desu>
Component: Power management & brightnessAssignee: Plasma Bugs List <plasma-bugs>
Status: RESOLVED DUPLICATE    
Severity: normal CC: kdedev, zeertzjq
Priority: NOR    
Version: 6.2.4   
Target Milestone: 1.0   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description cantabile 2019-11-25 16:54:48 UTC 
SUMMARY
If I plug in or unplug the laptop's AC adapter after the screen has gone to sleep the screen will wake up and the backlight will be at 100%, no matter what the brightness level was before the screen went to sleep.

STEPS TO REPRODUCE
1. Lower the backlight brightness to something visibly less than 100%
2. Leave the system alone until the screen goes to sleep
3. Plug in or unplug the AC adapter.

OBSERVED RESULT
The screen wakes up and the backlight is at 100% brightness.

EXPECTED RESULT
The screen should wake up and the backlight should be at whatever level it was before the screen went to sleep.

SOFTWARE/OS VERSIONS
Linux: Arch Linux
KDE Plasma Version: 5.17.3-1
KDE Frameworks Version: 5.64.0-1
Qt Version: 5.13.2-3
xorg-server version: 1.20.5-4

ADDITIONAL INFORMATION
The laptop is HP 250 G7, model 6MQ29EA. It has Intel Core i3 7020U:

00:02.0 VGA compatible controller [0300]: Intel Corporation HD Graphics 620 [8086:5916] (rev 02)

And the screen:

Manufacturer: BOE  Model: 687  Serial#: 0


I don't have this problem on an older HP Compaq 6720s laptop, which has Intel 965 GM(E?) graphics.
Comment 1 cantabile 2020-10-18 20:14:02 UTC 
This problem is gone since I updated to Plasma 5.20, Linux 5.8.14, etc.
Comment 2 zeertzjq 2021-03-01 01:21:55 UTC 
I also have this problem.

Linux: Arch Linux
KDE Plasma version: 5.21.1-1
KDE Frameworks version: 5.79.0-1
Qt version: 5.15.2-5
xorg-server version: 1.20.10-3
Laptop: Lenovo ThinkPad T14
Comment 3 TraceyC 2025-03-06 18:26:23 UTC 
Are either of you able to reproduce this on Plasma 6.3.2 or later?
Comment 4 TraceyC 2025-03-06 18:28:04 UTC 
Actually, this looks like a duplicate of 494408, which was fixed. If you're still experiencing this bug, please open a new report. Thanks!

*** This bug has been marked as a duplicate of bug 494408 ***