Brightness issue

Help
1

Hello there, I am facing a brightness issue on plasma 6. When I turn on the system, the brightness is set to the level of the previous session (on the screen with the laptop logo), but as soon as I reach the lock screen, it is set to maximum every time. What can I do to solve this? Will fixes be implemented in the future? To confirm that it is not a problem with my laptop, I checked with Gnome and it does not happen to me… I look forward to your news and thank you!
PS: sorry for my bad eng

2

Hi, thanks for dropping by and your English is very decent.

I don’t have a good answer for you right now. Plasma does not have code to set the screen brightness on the lock screen. We have code to set the brightness:

  • On manual changes, which is usually via Brightness applet or brightness keys on some laptop keyboards.
  • Automatically after a period of inactivity, which will dim the screen. The original brightness gets restored when you e.g. move the mouse or press a key.
  • When switching between plugged-in and on battery (or low battery), to a fixed value that can be configured in System Settings in the Energy Saving settings module. By default, Plasma only does this when reaching low battery.

So we’ll want to find out why something happens on your lock screen anyway.

But first, let me ask what exactly you mean by “lock screen”. Does your brightness get set to max:

  • Right after booting up, when you have to select a user and enter the password for the first time? (We call this the login manager. Usually a KDE distribution will include or recommend SDDM as login manager, which strictly speaking is not part of Plasma itself.)
  • Or after you have logged into your Plasma session for the selected user, when the screen gets locked after a period of inactivity? (We call this the lock screen, it has only a password field and a few extra buttons.)

Depending on which one it is, we’ll have to look in different parts of the code.

4

Hi thanks for your reply, I’ll explain better how you asked: The problem occurs when I turn on my pc, my distro( Fedora) in the screen with the logo of my PC (Lenovo Yoga 7) lowers the brightness to the level of the previous session. Once you get to the login screen (called by you login manager) the brightness is set to maximum and therefore even entering the desktop plasma remains at maximum. However, once I set a brightness with the applet or keyboard shortcuts, a new login from the lock screen does not change the brightness, which remains at the desired level. This can be summed up as the problem occurs the first time I log in to the login manager and that it is also perpetuated in the desktop plasma until I change it. Thank you for your help!