Icons are doubling in my panels

Something is really screwed up with my panels. When I add icons, the next day some of them have doubled. When I remove one of the two icons, they both are deleted.

Any clues as to what is wrong?

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Thanks.


I would recommend to open MATE Tweak and change Layout of MATE Panels to Traditional and then back to your favorite. It will reset all the MATE Panels, so then you'll need to carefully place icons and applets in their places again.