Bug 496952

Summary:	Whenever the station is locked, the additional (second) display brightness adjustment disappears.
Product:	[Plasma] plasmashell	Reporter:	Thiago Girolamo <thiago.girolamo>
Component:	Brightness and Color widget	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED DUPLICATE
Severity:	minor	CC:	kdedev, natalie_clarius, nate
Priority:	NOR
Version:	master
Target Milestone:	1.0
Platform:	Fedora RPMs
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Thiago Girolamo 2024-12-02 18:25:05 UTC

SUMMARY
Whenever the station is locked, the additional (second) display brightness adjustment disappears.

STEPS TO REPRODUCE
1. Lock session
2. Try to adjust brightness
3. There is no adjustment for the second screen (Samsung F24G3xTF)

OBSERVED RESULT
There is no adjustment for the second screen, just for built-in laptop monitor (Thinkpad P14s Gen4 AMD)

EXPECTED RESULT


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora rawhide 6.13.0-0.rc0.20241126git7eef7e306d3c.10.fc42.x86_64 | Plasma 6.2.4
KDE Plasma Version:  6.2.4 
KDE Frameworks Version: 6.8.0
Qt Version: 6.8.0


ADDITIONAL INFORMATION
Wayland 6.2.4-1.fc42

Comment 1 TraceyC 2024-12-10 19:57:23 UTC

I can reproduce this on Plasma 6.2.4
I'm not able to reproduce this on git-master, it looks like this has been fixed and will be available in 6.3

I want to make sure we're talking about the same thing. Are you talking about the indicator *on the lock screen* showing the brightness of the screens when you change it? (As opposed to Brightness and Color in the system tray)

Comment 2 Thiago Girolamo 2024-12-10 20:03:27 UTC

(In reply to TraceyC from comment #1)
> I can reproduce this on Plasma 6.2.4
> I'm not able to reproduce this on git-master, it looks like this has been
> fixed and will be available in 6.3
> 
> I want to make sure we're talking about the same thing. Are you talking
> about the indicator *on the lock screen* showing the brightness of the
> screens when you change it? (As opposed to Brightness and Color in the
> system tray)

I'm talking about Brightness and Color in the system tray

Looking at $journalctl --user -xeu plasma-powerdevil.service

the issue seems to be related to this:

org.kde.powerdevil: [DDCutilDetector]: Failed to initialize callback

After reinitialize plasma-powerdevil.service I can adjust brightness again, but after a idle lockcreen I can see the same behavior again

Comment 3 TraceyC 2024-12-11 01:46:15 UTC

Thanks for the clarification. I was not able to replicate this in the Brightness and Color applet on git-master with Wayland
I was also not able to replicate on 6.2.4

System:
Laptop connected to external monitor, logged into Wayland session

(With X11, even with a reboot I don't see the external monitor, just the laptop display)

I'll leave this open in case someone else can replicate. This could be affected by different hardware.

Comment 4 Nate Graham 2024-12-11 21:50:30 UTC

*** This bug has been marked as a duplicate of bug 482713 ***