Hi,

Is there a single key that displays the preview window, and then back to the editor?

I know we can do a split screen, but I want to see one at a time.

sorry, there is no shortcut

Ok, thanks dmitri.

Have a look at autohotkey https://www.autohotkey.com/ as that has some quite clever capabilities for creating your own shortcuts.

I doubt it will help because -- tabs here are custom components I developed from scratches. They have nothing to do with standard tab controls.
I'll add shortcut -- it's not a big deal. The only problem is choosing a shortcut that is comfortable and that is not already used.