Rated 5 out of 5 stars

The Firebug Add-on for Firefox is quite simply the best tool a web developer can have at his or her disposal. The ability to examine every facet of the DOM, CSS, HTML, JavaScript, client requests and server responses has enabled me to debug every problem I have ever run into the development process. I simply cannot develop a website without Firebug in my toolbox.

This review is for a previous version of the add-on (1.9.1).