Great Add-on; stopped working in FF 16.0.1 Rated 5 out of 5 stars
Love it! However, it stopped appearing in the FF 16.0.1 release. In fact, I sent Mozilla a message..one of those..made me unhappy remarks. Honestly, I want this thing working!This review is for a previous version of the add-on (2.0.1-signed.1-signed).
Probably a problem on your side
I'm fairly confident that it's a problem on your Firefox/machine. Add-on has been tested on 16.0.1 on various machines and shows no signs that you describe.
Try uninstalling the add-on and then installing again, check if you maybe forgot the button inside "Customize Toolbar" window (even though since version 2.0 it should add itself automatically), check if some other add-on is causing the problem, ... it could be anything.
You can also try installing some older versions of the add-on to eliminate the possibility that only 2.0 breaks for you. Here's a link: