Where is my twitter tab bar icon?

So I recently downloaded the new Mozilla Firefox add-on that is supposed to add a twitter tab permanently to your list of tabs. When I installed it, it showed up perfectly fine, no screw ups, but after I had exited the browser and went to bed, I woke up and it was no longer pinned to the tab bar. I went into my list of add-ons, removed it, reinstalled it, and still nothing pinned to it. Can anyone tell me how to get it back?