When I open mutt any folder containing new emails says (1) regardless of how many unread emails are in the folder. Once opening the folder the number will update. Once I close mutt and open it again it goes back to just (1).
If I downgrade mutt to the previous version and go back to the original Terry P. Chan patch which I'm assuming this is based off of, it works as expected.
+1, happens for me too
Works for me on a recent build.