I use the "todo" tag for books / movies / etc I want to read or watch. When I have spare time I search "My library tagged: todo" to find stuff and remove the tag when I'm done with something. Recently, this does not work as expected anymore: I can remove the tag and it is gone from the bookmark (not visible any more in bookmark listing or bookmark edit mode), but it is still in the search results for "tagged=todo". Also in the "related tags" sidebar, there are whole tags listed which are not used anymore, such as "test".

This might be related to the issue a couple of weeks ago where tags could not be edited any more...