Simple Edit for FF 3.6 Rated 5 out of 5 stars
This is probably one on my most used add-ons. I do not think there is a day I do not use it. I was disappointed when it did not work for version 3.6 But then I followed the instructions carefully at http://kb.mozillazine.org/Editing_an_add-on_to_change_its_compatibility and it worked like a charm!!This user has other reviews of this add-on.