I like this add-on a lot and have used it for some time now... albeit in the older format not compatible with the newer FF versions. I'm slightly embarrassed to admit that one of my PC's only was upgraded to the latest FF as of yesterday because I wasn't aware of this Greasemonkey work around.
Well I was a bit scared at first, the old version of this uses a menu item in the right click to open the neg/neutral feedback in a new tab or window. This script doesn't do that, instead it creates a little icon that you click on beside the "Detailed Feedback" link. This mini review is a note for others that might be in the same position I was in. It works the same as the old, just a bit differently.
You could comment on this review if you were logged in.