21.10 screen dim problem


I'm using 21.10 Mate on my computer (this is the first version which runs on my computer since 16.04). (7200U, onboard vga)
I'm happy with it, stable, but when i leave my computer turned on for a while and leave alone it starts to dim the screen . The dimmed screen is steady until i reboot, so i have to reboot every morning.
I cant figure out where can i disable this "feature".

The screen shots will be a little different on 20.10 but the places to adjust the power management and screen saver settings will be the same. You will need to adjust both to eliminate the dimming and/or screen saver.

In the title you mention 20.10 which is EOL ; see

however you mention 21.10 in your actual post. One is likely a typo, it may help everyone if you correct the one that is wrong. Thanks :slight_smile:

I've just corrected it. 21.10 is the correct.

The dim function is turned off in the power management menu but it does the same.
Its sure not the power management does thing, because it wont get brighter if i press a key. Just the reboot helps.

Just a thought.
There were cases when power/screen management in BIOS caused problems actually.

In "21.10", once the screen saver has started, the entire screen is dimmed and I can't change that without rebooting. This is not acceptable.

It is a side-effect of bugs in mate-screensaver and mate-menus:

Please subscribe to both and mark yourself as affected.

Possible workaround is to remove MATE Screensaver and temporary replace it by XScreenSaver:

sudo apt-get purge --autoremove mate-screensaver
sudo apt-get install xscreensaver

systemctl --user enable xscreensaver.service
systemctl --user start xscreensaver.service

then test it using Ctrl+Alt+L.

Reverting to default screensaver is possible by

systemctl --user disable xscreensaver.service

sudo apt-get purge --autoremove xscreensaver
sudo apt-get install mate-screensaver ubuntu-mate-desktop ubuntu-mate-core