Download Facebook Video 2.1.8 FireFox Addon not working with FireFox 3.5.6

The popular Greasemonkey download Facebook video script which is a full-fledged Firefox addon that lets users download or convert Facebook videos, and embed videos outside of Facebook is not working with latest update of firefox 3.5.6. So If you want to download videos from facebook do not upgrade your firefox browser to 3.5.6 unless a fix is announced by the plugin author.