Okay, we all know how the "Normal" Firefox has the Menu Bar (File, Edit, View, etc.,) integrated with the taskbar at the top of the screen, just like every other program in Ubuntu (with the exception of programs run with gksu.)

Now, I downloaded and installed the Nightly build of Firefox, and have been using it via the launcher (I finally figured all that out!) but whenever I run the Nightly build, the menu bar is separate, like so: http://i.imgur.com/Xogbs.png

How do I fix this? I remember there being some sort of extension that did that, but I can't find it anymore.