this was because of a tag with "/" in it in my bookmarks
I suppose any tag with the "/" in it will just break the entire bookmarked tags functionality
i was able to remove it from bookmarks by fucking around in the dev console and now things work: Fine
Izzy Otter
or, on any other page, the current url plus # (see attached screenshot) and as a result cant get to the list of bookmarked tags to change it in bulk, only way to interact with the list is to navigate to indiv tags and bookmark/unbookmark them there