If you’re the kind of person who regularly runs Firefox with multiple tabs open, you might find keeping track of which website is where challenging. In those circumstances, Tab Scope for Firefox is the perfect add-on for your needs.

Tab Scope for Firefox allows you to preview any tab by rolling the mouse over it, just like the Aero Peek feature in Windows Vista and 7. A small pop-up preview of that tab’s contents will appear, allowing you to quickly locate the tab you’re looking for. But while that’s impressive in itself, there’s more: not only does Tab Scope provide you with some handy shortcuts for that tab via its preview window, it’s also infinitely customisable too.

Keep the mouse pointer held over a preview window and you’ll see a toolbar appear at the top of the page – use this to navigate or refresh the contents of the tab without opening it. Right-click the window to double its size, making it easier to read the content within, while you can also convert the tab into an App Tab or open the Group Tabs window directly from here too.

If Tab Scope looks promising, but doesn’t quite fit perfectly in with your needs, take a trip to its Options screen, where you can do just about anything to it you like: set the default preview window size and the magnification level to apply when right-clicking the window. Set the preview window to appear above or to either side of the tab as opposed to beneath it, and then switch to the Advanced tab for even more fine-tuning, with the ability to configure how each mouse button (left, right and middle) will work when clicked.

It all adds up to an incredibly useful extension, efficiently written (it’s only 56KB in size) and one we’re happy to add to our list of top Firefox extensions. Tab Scope for Firefox is a free extension suitable for any flavour of computer running Firefox 3.6 or later.