How to exit fullscreen monitor playback in Premiere? In Premiere Pro 2017 (Windows 10) in Preferences -> Playback I can set one of my monitors as the playback device



Now when I playback video it will appear full screen in one of my monitors.  When I hit stop (spacebar) the video is still full screen.  How can I exit or quit this full screen playback mode?

I tried the obvious of hitting Esc but this does nothing.  Is the only option to go back to preferences and uncheck it? (Also how do I know which monitor is which?  Not knowing how to exit the fullscreen mode I'm a little paranoid that I will choose the same monitor that the Adobe UI is on and then be stuck.)
As far as I am aware, there isn't a way to disable Mercury Transmit if the viewer covers the UI, unless you set up a key binding. You can assign a keyboard shortcut to the "Enable Transmit" function in the keyboard preferences (I use ctrl+shift+' as it's similar to the maximise window shortcut). You can then use this key combination to toggle the full screen display on and off.