Firefox 10 adds built-in dev tools
 

With major new versions of Firefox and Chrome rolling out every few weeks, it's easy to tune them out. Believe it or not, though, the latest Firefox release actually has a couple of noteworthy new features.

First are the new developer tools, which replicate the functionality of the popular Firebug extension and similar tools built into Internet Explorer, Chrome, Safari, and Opera. Those tools proved particularly invaluable when I was working on TR's new design, since they let me test tweaks to our CSS stylesheet ...

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