Is it possible to completely hide the menu bar on an external monitor? I'm using my laptop with a projector, and while I can set the desktop background to completely black, the menu bar is still there. Even in dark mode there is still text. I would like to avoid showing any desktop UI if the presentation (Keynote) exits.
I think it's possibly 'Displays have separate Spaces' in System Prefs > Mission Control.
I've had that switched off since it was added to prefs, & only have a menu bar on my main monitor.
I don't want to switch it back to test, it messes things up ;-)