Firefox OS Simulator is a test environment for Firefox OS. Use it to test your apps in a Firefox OS-like environment that looks and feels like a mobile phone. After installing it, go to Web Developer > Firefox OS Simulator to access its features.
Help make Firefox better. The Add-on Compatibility Reporter enables you to report if the Firefox add-ons that you're using are working properly.
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
Useful tools for the nightly tester.
Firesay enables you to surf the web using voice commands.
Say your search queries instead of typing them.
Say which sites you want to visit instead of typing URL addresses
Say "Firesay, share on Facebook" to share any page on Facebook