How do you do this in Xorg? Is there some script that runs in response to xset? Right now, I use
intel_backlight 1 to keep my laptop display almost off when using an external monitor. After an idle period of 10 mins (set in KDE5 "Power Management / Energy Saving") , both displays switch off. When I come back and wake the screen, the laptop display is reset to a blinding 100 percent brightness. How can I preserve this backlight settting? I don't see anything in xset--assuming this is how KDE is doing it--man page about running a script on wake/sleep.