So you should dim the brightness on every time you logged in. What a hell?!
I've suggested the workaround for it:
When a user logged in via display-manager, before reach for the session kick, system must be recovered from the previous brightness setting.
Sometimes "sudo echo xx > /sys/class/backlight/..." were reported on somewhere, but it's not smart. yeah it might need something like root access right. So we could use "pkexec" system instead of direct access to class files...
- If you had any ACPI based backlight on /sys/class/backlight/, Check your favorite value of brightness.
- Or if you had some platform special backlight, Also check your favorite brightness value.
- Register a new "startup application" to control brightness via pkexec:
For example, mine has "max_brightness" as "15", so that meant I prefer to startup with "a falf brightness". I think this method is really easy to register and load. :)