Mozilla Firefox is a user-friendly, extendable web browser. It features popup blocking, tabbed browsing, RSS integration as well as support for CSS 2.01 and XHTML. It is open source and cross-platform.
HTML and XHTML
- The HTML 4.01 Specification is fully supported.
- The XHTML 1.0 Specification is fully supported.
- The XHTML 1.1 Specification is fully supported, even when correctly served as
- CSS 2.1 Specification is mostly supported. CSS 3.0 support has already been started, notably the opacity property.
Extensions are small add-ons that add new functionality to Firefox. They can add anything from a toolbar button to a completely new feature.
Live HTTP Headers
The Live HTTP Headers extension adds two features to Firefox that are useful for web development. It adds a new Tool that allows one to monitor HTTP request and response headers as requests are being processed. It also adds a Headers tab to the View Page Info window with panes for the HTTP request and responses headers.
The Firebug extension offers a huge number of tools for web designers, including real time CSS and HTML debugging.
SEO For Firefox
Want to know why a particular site ranks on Google or Yahoo!? Aaron Wall's SEO For Firefox extension takes data from a huge range of sources (including Yahoo backlink counts, DMOZ listing and Compete.com) to illustrate at a glance why a site rnaks.
The Domain Lookup for Firefox extension lets users perform one click domain lookups at DreamHost and 30+ other registrars. It uses the selected text in your Firefox window as source text.