Windows 10: Stubborn grey rectangle covering up the upper left of the desktop

After I tried adding a virtual desktop, a strange gray rectangle has appeared on my desktop (both Desktop 1 and Desktop 2 I might add). This semi translucent rectangle covers up the desktop icons so that I cannot click on them.

I've tried to close all apps, but it won't go away. Any idea what this is all about?

-Rune


EDIT: Never mind. It disappeared with a reboot.

:)

 

questionable image on all screens

Please see the image below that demonstrates the black rectangle with the blue line and "100" that mysteriously started appearing on the upper left portion of my screen on documents, desktop and websites. I am unable to move it or delete this black rectangle
despite searching through all of the programs and controls. Please advise.

 

How to disable grey rectangle in middle of computer screen- fixed.

How do I get rid of a rectangle, 2x1 inches in middle of screen. Grey in colour. Cursor goes under it. We have turned off computer. No good still there. We are having to work with it but it is difficult. we do not know how to disable. we cannot move it
out of the way.