[slightwinder]

> The addon doesn't have the concept of named groups

Actually, it has, but it's seems to lack UI-Integration for whatever reason. I use this bookmarklet for some years not to create a Group-Tab:

javascript:(function(){window.open("ext+treestyletab:group?title=NewGroup&temporary=false")})();

To rename it, just click the title inside the group-tab.