F1 by Mozilla Labs  is not a URL shortener instead this extension allows to share links on twitter, Facebook, and Gmail from with in the browser, from any webpage  fast and easy. F1 by Mozilla Labs  automatically shortens URLs using bit.ly and inserts the shortened URL into your tweet for twitter.

F1 by Mozilla Labs extension

After installing F1 by Mozilla Labs you need to add  your Twitter,Facebook, Gmail accounts to share links. After adding your account for particular service, click F1 by Mozilla Labs icon appears after search bar and F1 shows empty box to enter your description.

For Facebook, F1 posts the URL complete with screenshot and description right into your Facebook Wall ,instantly share the link with all your friends on Facebook.

For Gmail F1 automatically inserts the URL into  the  body of your email, simply type in your recipients Email addresses and hit share.

F1 by Mozilla Labs is made by Mozilla Messaging.

F1 by Mozilla Labs works with Firefox 3.6 and Firefox 4.0 .