Brightness value set is lost if the screen is rotated with xrandr
This issue is seen only with gnome (kde and lxde is not affected).
Change Brightness: xrandr --output HDMI-1 --brightness 0.2
Change orientation: xrandr --output HDMI-1 --rotate left
Brightness is reset to 1.0 if we rotate the screen.
xrandr program version 1.5.0