Please add support for FF4 Rated 5 out of 5 stars

Thank you for this great extension! Screen utilisation is essential to me. Please make this extension available for FF4. I'm willing to donate for your efforts.
A great improvement would be a hotkey to hide/show the vertical tabbar. I have installed "Hide Tabbar" for this, but it is also not supported for FF4.
Most web pages have fixed width. Modern displays have plenty of unused space on the left and right side. Tabs on top are a waste of the precious vertical space. Even when I have many tabs open, with VertTabbar the tabs are still readable.