Rated 4 out of 5 stars

see also comment below.
Unfortunately, can't follow re - messages.
That happens even if there is no re in the subject line. It seems TB or the addon get that elsewhere.

That really is a pity - 80% of my emails are a re on some other message.

This review is for a previous version of the add-on (0.6). 

Rated 4 out of 5 stars

in a communication tree, soon there is a collection of
messages -re --re re --- re re re etc.
If I answer a single email and my mail starts with re: subject, it is immediately noted as 'already replied to' after sending. Doesn't wait for actual replies to come in. Win 7, newest TB.

For messages without re: very convinient addon

This review is for a previous version of the add-on (0.6).