Rated 5 out of 5 stars

It works great with FF 21, only one issue when you set the "Auto hide tab bar" option and then when you hover over it, for the blank area it shows the resize component. Its a minor one though but you can look into it..
But I must say that its a new thinking. Great work.. :)

This review is for a previous version of the add-on (0.14.2013052901).