As described in the answers to other questions, I am aware of the "Displays" settings where I can disable my laptop monitor. That works fine.
However when I reboot, my laptop monitor is magically re-enabled and I have to go to the Displays settings and disable it again. Is it possible to make this setting persistent?
It used to work fine on 14.04, but for some crazy reason I upgraded to 16.04 and it hasn't worked since then. Also 14.04 had this nice behavior where if I turned on my laptop without my external monitor plugged in (or if I unplugged my external monitor), then the laptop monitor would turn on. I'd like a solution that maintains that functionality too.
I'm using gnome-session-flashback, if that makes a difference. Graphics are Intel HD Graphics 4000.