Rated 4 out of 5 stars

It lacks just one thing: domain wildcard photos.These photos should be assigned to an entire domain and displayed if there is no other photo to show.The file name should be composed of an @ sign followed by the domain name and the file type (e.g. '@mozilla.org.png').Or it should be downloaded as favicon.ico from the base mail domain (e.g. 'www.mozilla.org/favicon.ico')...

This review is for a previous version of the add-on (0.9). 

file wildcard should be easy as we already support avatar from local dir.