Highlight closed navigation entries with open sessions.

Not exactly sure of the terminology, but the navigation list can get pretty long, especially if you only have one or 2 sessions open in each group. So for long running sessions, I like to hit the little >v thingie, and collapse the entries for less scrolling, but it would be nice if when a session was open in one that was >, it would be bolded or highlighted or something to tell you there's an open session in that group.