Rated 5 out of 5 stars

Dev is super responsive in replying and fixing stuff.

This review is for a previous version of the add-on (2.0.7). 

This is definitely conflict with some of the addons that you also have installed. If you need a help to solve this problem, write the details on support forum - http://forums.mozillazine.org/viewtopic.php?f=48&t=2972255