I had problems with the tags drop down menu too but thought it was just a problem on my end with where I was opening the menu ... I'm using Firefox. Just checked and the problem I was having is no longer occurring ... dunno if it's related or not.
We updated one of the libraries which resolved/improved a couple of things. During testing however we missed this issue. We're still working on it and would rather see it fixed than having to do a rollback.