Explorer ribbon blocked / 90% hidden after update

I had an overnight update install itself last week.  After the AM reboot, the Windows Explorer window has been altered, such that the ribbon is now hidden the the content frame (not sure about my terminology; please see attached screenshot).  The tops of the buttons are barely visible, but hovering over them, some are active.  Rebooted many times, no diff.  Compact view on or off makes no difference.  I believe I tried safe mode, no diff (I'll try again).  

My tech support source got on the machine and rolled back an update, but no difference.  I've uninstalled some useless demo apps, etc, no difference.  I don't believe there are any more updates that came that night to roll back.  My skill levels are approximately "old school power user."  NOT tech support level. I would be grateful for any suggestions; it's not shutting me down, but it's getting fairly tedious.  

And aside, kind of personal mantra now:  "It was working before; why did you break it?"