"Firefox 3.7a5pre now has an option to place the browser's tabs on top of the controls, similar to Google Chrome. This is likely part of Mozilla's plans to redesign Firefox for version 4." ... "Firefox 3.7a5pre handles the Add-ons window differently, as it opens in a new tab rather than a new window. The Add-ons Manager has also been redesigned and has animations such as "Search" sliding in the left column when you search."