Rated 5 out of 5 stars

Sounding like a broken record here... Have been using--and loving--this add-on since Firefox 4. However, it no longer works with Firefox 13. Please fix!

You can try the alpha (incomplete) version:
http://joliclic.free.fr/blog/index.php?post/2012/06/15/Boox-31-alpha-1-for-Firefox-13