Kubuntu GUI display configuration tools (both in systemsettings and the separate krandrtray application) will not automatically revert to their previous display configuration. If the display configuration is set to a non-working configuration, other tools will have to be used to reset the display to a working configuration either by connecting to the system via SSH or rebooting into recovery mode. For example, using xrandr, you can determine the current configuration using:
DISPLAY=:0 xrandr --current
and then change the configuration to a safe mode using:
Proposed release note:
Kubuntu GUI display configuration tools (both in systemsettings and the separate krandrtray application) will not automatically revert to their previous display configuration. If the display configuration is set to a non-working configuration, other tools will have to be used to reset the display to a working configuration either by connecting to the system via SSH or rebooting into recovery mode. For example, using xrandr, you can determine the current configuration using:
DISPLAY=:0 xrandr --current
and then change the configuration to a safe mode using:
sudo DISPLAY=:0 xrandr --output [DISPLAY NAME] --mode [NEW RESOLUTION]
sudo DISPLAY=:0 xrandr --output VGA1 --mode 2048x1536
See man xrandr and xrandr -h for more information.