I have folders marked as favorite and I cannot unmark them. When I open the context menu, I can mark it as favorite (even though it already is) and then unmark it, but the star next to the folder icon stays.
Since I updated to the latest version, I can mark and unmark new folders at first without any problems, but later not anymore.
I think the only thing I did was filtering on the favorite folders only followed by trying to unmark a folder while the filter is active. Afterwards its not working for any folder anymore.