Composition Mode (full screen) stopped working

I’ve recently purchased a new laptop and installed Scrivener. For several weeks, everything worked relatively fine, but the last couple of days, I’ve been unable to get the full screen (Composition Mode) function to work. When I try to make my document full screen, it clearly tries to do it, flashing the control strip across the bottom of the screen momentarily (blink and I’d miss it), but then reverts back to the normal view (binder on the left hand side, ribbon at the top).

I’ve just uninstalled and reinstalled the program, but that didn’t fix it. Please help!