A possible bug with WP 20 and Antidote

I recently installed Antidote, a French language corrector, grammar checker etc with the English manual. I noticed a weird bug with WP, I open multiple documents. I then work on them and save the workspace. When I then reopen  WP,. I get a message that the files are being currently used or read only.  SO I close WP 20 So on a whim I took a look at Task manager and I see that WP 20 is still open. I end task then open WP 20 and voila the saved workspace loads as if nothing happens.

My Windows 10 64 bits is ii French and so is my WP 20. Antidote is up to date. Could the programmers take a look and confirm if there's a bug?