Firefox 11 released with Style Editor and 3D DOM viewer: 

Today Mozilla has released Firefox 11 with all new Developer Tools and Add-on Sync function. Since last year Mozilla made some quick updates of it’s browser versions. Just two months ago Mozilla released Firefox 10 and within less than a month it again released Firefox 11.

Improvements in Firefox 11

• The built-in style sheet editor in Firefox 11
• The 3D DOM visualization tool in Firefox 11

Download Mozilla Firefox 11 from here

Upgrade to latest version of Firefox (Currently Firefox 11) as soon as you can. This will help you to avoid various security threats, and stay safe online.