I have noticed in map compare several of the filters will remain even after they are removed from a search. Specifically custom filters, show disabled/archived, and possibly others. The filters will not show as visible on the map compare page but when you hit "filter" to display results, they will show up in the search.
Then when you navigate back to the previous page, they will be visible on the map compare page. Sometimes you have to go back and forth 2-3 times between pages before the filters are gone.