Firefox extensions are software plugins that add new features to the Mozilla Firefox web browsers.
Most Firefox extensions work in the SeaMonkey web browser as well. For a more technical description, see Extension (Mozilla).
This is not a complete list. For a more complete list, see http://addons.mozilla.org.
Most of these extensions are open-source software, but some are not, including 1-Click Weather and the Google Toolbar for Firefox.
- 1-Click Answers provides quick access to Answers.com definitions of highlighted words.
- 1-Click Weather The Weather Channel's version of Forecastfox but with more features
- Adblock or its variant Adblock Plus is used for blocking ads.
- Adsense Notifier (more info) is an extension that allows Adsense publishers to display their earnings on the Firefox toolbar.
- Advanced Dork:(more info) Provides right-click functionality to highlighted word or phrases for immediate use with Google’s Advanced Operators.
- All-in-one Sidebar (more info) is a sidebar control, inspired by Opera's. It lets you quickly switch between sidebars, view dialog windows such as downloads, extensions, and more in the sidebar, or view source or websites in the sidebar. It includes a slide-out button and a toolbar, all of which can be extensively customized.
- Bookmark Backup creates an automatic backup of bookmarks each time the browser is closed, which can be restored in the event of profile corruption.
- ChatZilla is a full-fledged IRC chat client that works inside Firefox.
- ChromEdit is an editor that allows you to edit various configuration files from within the browser. Files you can edit are UserChrome.css, UserContent.css, User.js, and Prefs.js.
- CookiePie (aka ChocoTorta) is a Firefox extension to have different mails accounts (Gmail/Yahoo!/etc) or application profiles on each tab.
- Copy Plain Text Does exactly what its name implies. Also good for copying tables to excel. More Info
- CustomizeGoogle adds features such as Google Suggest and Yahoo! and Internet Archive links to Google search results pages. It also can remove ads.
- CuteMenus Crystal SVG (download) adds colorful icons to Firefox's menu items.
- digg.com toolbar (download) Toolbar for the social bookmarking website digg.com. Contains many rss feeds, search digg, submit to digg button, digg.com chat room and links to every diggnation broadcast.
- DOM Inspector is for web developers. It allows them to inspect the Document Object Model tree of any page.
- Farkit is a plugin for Mozilla Firefox which makes replying to comments on Fark easier. (download)
- Fasterfox prefetches links on pages to make firefox browsing a faster experience
- Feedview allows Firefox to open RSS and Atom feeds as webpages.
- Firefox Extension Backup Extension (FEBE) backs up your extensions, themes, and (optionally) your bookmarks, preferences and cookies. (More info/download)
- Flashblock prevents Flash movies from playing without explicitly starting them or adding the originating site to a whitelist
- FlashGot (more info) provides massive download features (like downloading all link or selected links from a page at once) and seamless integration with several external download manager programs.
- Forecastfox (more info) is a Firefox browser extension created by Jon Stritar and Richard Klein that displays a summary of weather forecast for a given location in the status bar, menu bar or toolbar. The summary takes the form of icons depicting sun, clouds or rain for one or more days ahead. Hovering over the icons shows more information such as temperature and wind speed. Forecast information is provided by Accuweather. Previously, the feed was provided by Weather.com but the terms and conditions became too restrictive. See also 1-Click Weather, above.
- FootieFox displays live soccer scores in the statusbar and notifies you in case of a goal. (more)
- Google Browser Sync allows users to store firefox bookmarks, history, persistent cookies, and saved bookmarks on googles servers so that when using firefox on a different computer that information will be the same on all computers.
- Google Notebook allows users to access the service without navigating away from their current webpage, allowing highlighted text and images to be added to a user's notebook without the need for copy-pasting.
- Google Toolbar for Firefox has identical functions to the Google Toolbar.