Rated 5 out of 5 stars

Works perfectly on GNU/Linux. The other add-ons in this category can't even compare. Would give 6 stars if I could!(I also have looked through the source and it is clean.)

EDIT: August 22 2013

The add-on is working again perfectly, thank you dev!

This review is for a previous version of the add-on (1.0.1.1-signed). 

Please use version 1.0.3 which fixes these problems. (see description)
The automatic update will not work for some time, because each version of the addon has to be reviewed by mozilla to enable the automatic update.