MDN’s new design is in Beta! A sneak peek: https://blog.mozilla.org/opendesign/mdns-new-design-beta/

Use the Page Inspector to examine and modify the HTML and CSS of a page.

You can examine pages loaded in the local copy of Firefox or in a remote target such as Firefox for Android. See remote debugging to learn how to connect the developer tools to a remote target.


User Interface Tour

To find your way around the Inspector, here's a quick tour of the UI.


How to

To find out what you can do with the Inspector, see the following how to guides:


Reference