systemd-backlight@.service, systemd-backlight — Load and save the display backlight brightness at boot and shutdown
systemd-backlight@.service
/usr/lib/systemd/systemd-backlight
systemd-backlight@.service
is a service that restores the display backlight
brightness at early-boot and saves it at shutdown. On
disk, the backlight brightness is stored in
/var/lib/backlight/. Note that by
default, only firmware backlight devices are
saved/restored.