I set TB so that it never flag emails as read but when I explictly set them as Read.
However, whatever being the TB settings, I believe that when you have your view filtered by "Unread only" and you explicitly (i.e. manually) set an email as "Read", it would be very useful that TB updated the view in realtime (and possibly move on the next mail).
Currently, you have to remove the filter and apply it again, and that's a bit unpractical (at least in my daily usage).
Thank you so much to the developer for this great piece of software 🙂