Which FireFox addon is this?

I saw this video on Youtube and the person on the video was using this addon.



When he clicked on Forms it was able to show the source of the forum such as name and id. Does anyone know the name of the addon? Also is there also similar addon for chrome?

Thank You.

richardbraceros said:

http://chrispederick.com/work/web-developer/

Click to expand...

Thank You so much.