Could you add a shortcut to put an overlay over an image if a button pressed?
In a way similar to the arrows you have now.
Something like "q" immediately puts some neutral page or image over what's being displayed. Some page with some tabulated text or whatever. And then, if another key is pressed, then we are back to the image that was originally shown.
I think a "b" button that turns the screen black could be useful and easy enough to make.
I think a "b" button that turns the screen black could be useful and easy enough to make.