Share Your Interesting/Useful Browser App/Extensions: FIREFOX

[Simon]

Firefox is my daily workhorse browser.

These are the addons/extensions I have installed.

Web Developer extension (as Toby mentioned) provides many valuable tools.

DownThemAll lets you download all the links or images contained in a web page in just one click. Helpful in gathering content when zipped files aren't available.

SEOquake is a seo-tool that shows page rank, Google index, Alexa and many others. Keyword Density tool shows number of times a keyword or phrase appears on a web page. Also can highlight nofollow links.

FireForm is a Firefox extension that automatically fills in forms.
You teach FireForm once, then it fills in forms with just one click.

Live HTTP Headers adds 'Headers' tab in 'View Page Info' of a web page and a tool in the 'Tools->Web Development' menu to display http headers in real time. Also lets you edit request headers and replay an URL.

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