I’d like to confirm that I am experiencing this. Also the same behaviour as explained in this similar post.
http://forum.webflow.com/t/having-issue-to-clean-up-and-remove-classes/10598/14
I created button classes and I am trying to remove all of them to redo it all. They were used in several symbols which have now been unlinked and removed. I have removed every class from every button but still cant seems to clean up the styles.
Would be nice to have a delete option in the edit classes panel. It would obviously be disabled if it had dependancies but if not the delete button would be active.