Rated 5 out of 5 stars
This is an *excellent* add-on for StumbleUpon users. It keeps all common tasks very conveniently located in a StumbleUpon toolbar that can be displayed or hidden with a hotkey.
I miss this add-on terribly after upgrading to Firefox 4.0b6. While the add-on seems to function, it causes other extensions' toolbar buttons to disappear. I can't wait for official support for Firefox 4.0.