Tried to style edit https://musicbrainz.org/release/9ab96a82-f13d-3bc0-ba96-8d97ef6384b3

Received error message “This medium is set to a format that did not exist on the selected release date”.

No issue with that message (though it would be nice if it was on the front display page and clicking on it led to more detailed information = Improvement).

The bug is that this prevents other edits.

These should only be prevented if the format or release date have been edited.