
Something to consider with screen Mirroring is the resolution of the external display, which is often different from the resolution set on a MacBook Pro or Air. Use this the next time you need to do a presentation, or watch a movie on a bigger screen, it’s super fast.

This command works with quite literally any Mac, whether a MacBook Pro, Air, iMac, whether it’s using a built-in or external keyboard, and with any connected secondary display, from an external monitor, a TV, a projector, Apple TV through AirPlay Mirroring, whatever.

In order for this shortcut to work you will need an external display of any sort attached, then once hit hit Command+F1 you will see both displays briefly flicker bright blue and suddenly mirroring will be enabled.
