I’ve been a huge fan of Firefox since the beginning of 2005. I was sceptical initially: after all, Internet Explorer is perfectly adequate, and, as it is still the dominant browser from a market share perspective, there’s value in experiencing the web as the typical person does. However, the impressive core feature-set and burgeoning list of extensions for Firefox won me over.
FlashGot – the definitive download manager for Firefox.
Clear Cache Button – adds a button to the toolbar to clear the browser cache. An incredibly useful tool for web development!
Tab Mix Plus – take control of and customise your Firefox tabs; ressurect closed tabs and browser sessions.
ColorZilla – advanced eyedropper, colour picker, page zoomer and measurement tools.
LinkChecker – check the validity of links on any web page.
HTML Validator – a page validator based on the W3C’s Tidy which shows the number of page errors in the status bar when browsing.