After a recent update, all video is stuck at about 20% brightness. POST, splash and login screens are normal, but once the desktop starts, I can barely read the screen unless I darken the room. I saw a problem like this in a very old post, where pkexec was missing, but that package is installed.
I am using a KVM box. In the system journal, I see
Did you check the settings of your desktop environment? Systemsettings?
I have tried adjusting, toggling and disabling several different settings, all to no avail. I tried to start XScreenSaver Settings. All that happens is the bouncing icon appears for a few seconds, then the process either terminates or crashes before opening a window. It is also interesting that no matter how Power Management Display and Brightness settings are adjusted, the Change screen brightness slider is always grayed out.
Perhaps impacted by this bug?
https://bugs.kde.org/show_bug.cgi?id=486067
For some reason, my update didn’t install the Brightness and Color utility. I installed it and found my monitors were set to zero brightness. I set them to a reasonable value and all is well.
Thanks for the update. Good to know that you were just missing the applet.
