Musescore 4 opens but no display on the screen

When I open a Musescore file, Musescore opens and the file loads but there is no Musescore display on the screen. Windows Task Manager it shows Musescore is running and if I hit the space bar, playback begins.
So far, I've tried factory reset several times, removed and reinstalled Musescore several times. I've removed all earlier versions of Musescore and any associated files.
It is like Musescore is casting to a non-existent second monitor.