I also have the issue (Mint Mate 18.2), and it is super annoying. Another "workaround" to restore the original functionality is to klick on the "Show Desktop" button, or to minimize any window which is open.
I also have the issue (Mint Mate 18.2), and it is super annoying. Another "workaround" to restore the original functionality is to klick on the "Show Desktop" button, or to minimize any window which is open.