My Dell Mini 9’s screen has turned dim. It’s still usable, but I would prefer it to be brighter. Pressing the Fn-[brighter] and Fn-[dimmer] keys pops up a window with a monitor icon and a % brightness indicator, which changes appropriately with each key press, but the screen itself remains constantly dim.
In the last use before the problem started, I plugged a projector into the VGA port. I couldn’t get the projector to work properly despite fiddling around in System Settings > Display. I suspect something got borked either by plugging in the projector or by fiddling with the display settings.