Rated 5 out of 5 stars

Works well. Needs qBittorrent support, and possibly multiple server support.

This review is for a previous version of the add-on (0.2.2.3.1-signed). 

qBT support is added in latest version.
To test it out you can download from here:
https://addons.mozilla.org/en-US/firefox/addon/bittorrent-webui-120685/versions/0.2.3.0