Framemaker 2019 window resizes constantly

While working in Framemaker 2019 on Win 10, the working window keeps changing size and blacking out.  I have to keep resizing the window so I can see anything.  I save a doc, the frame resizes to about 1 inch high by 2 inches across while blacked out.  Then I have to minimize the window, restore the window, then resize the window, until I save the doc again.  Then same thing.  

It seems to be a setting of some kind, because the Framemaker starts up in this annoying setting, and reverts to it constantly.  

Any ideas?  
Thank you