b3fa4a6cd8
It uses the org.gnome.SettingsDaemon.Power.Screen D-Bus API. Currently brightness set if the proxy is not ready are ignored; whether the brightness value should be cached and set once it appears or whether color profiles should be reapplied is yet to be decided. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2165>