Rated 3 out of 5 stars

Pretty good so far. This is a simple way of adding notes to single emails, and the toolbar icon changing color for messages with notes is cool. However, it gets three stars because you cannot add a note to a thread, only to a single message at a time.

Adding a note to a thread so that the note shows for all messages in the thread is a must.

This review is for a previous version of the add-on (1.6.0.2).