This page is dedicated to the Firebug 3.0 release. Read more to know why you should install it (currently in beta phase).
Firebug 3.0 (also known as Firebug.next) represents the next Firebug generation built on top of the native Firefox developer tools.
Firebug has always been an extension (Firefox add-on) and the natural next step is to build the next version on top of existing developer related features and APIs built into Firefox - and extend them. This way Firebug can utilize the existing platform infrastructure and get significant performance, stability and security advantages.
Firebug wants to complement Firefox’ built-in tools by adding new functionality, not compete with them. The next Firebug generation starts with introducing a new Firebug theme and bringing the great Firebug user experience with it.
Users don’t want two separate tools in Firefox - they want one great and powerful tool!
Firebug 3.0 is compatible with Firefox 36+