Most Popular Extensions

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Adblock Plus No Restart Featured

Blocks annoying video ads on YouTube, Facebook ads, banners and much more.

Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).

Rated 5 out of 5 stars (4,934)
20,572,265 users

Lightning Featured

Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.

Rated 3 out of 5 stars (1,862)
4,615,569 users

NoScript Security Suite Featured

The best security you can get in a web browser!
Allow active content to run only from sites you trust, and protect yourself against XSS and Clickjacking attacks.

Rated 5 out of 5 stars (1,496)
2,189,027 users

Ghostery No Restart

Protect your privacy. See who's tracking your web browsing and block them with Ghostery.

Rated 5 out of 5 stars (1,177)
1,450,377 users

DownThemAll! Featured

The first and only download manager/accelerator built inside Firefox!

Rated 5 out of 5 stars (1,599)
1,354,941 users

Web of Trust, WOT: Website Reputation Ratings

Find out which websites you can trust. WOT adds intuitive traffic light-style icons next to search results and URLs so you can decide whether to visit a site:
• Green – The site is trusted
• Yellow – Be cautious
• Red – Online threats detected

Rated 3 out of 5 stars (1,630)
1,036,589 users

Download YouTube Videos as MP4 No Restart

An extension that adds direct links to download YouTube videos as MP4 and FLV. It has a simple interface and it downloads videos directly from YouTube. The extension integrates with YouTube's interface and adds a download button below the player.

Rated 4 out of 5 stars (355)
992,648 users

FlashGot Mass Downloader Featured

Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.

Rated 5 out of 5 stars (494)
934,701 users

Element Hiding Helper for Adblock Plus No Restart

Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.

Rated 5 out of 5 stars (447)
742,549 users

Adblock Edge No Restart

Adblock Edge is a fork of the Adblock Plus version 2.1.2 extension for blocking advertisements on the web, without sponsored ads whitelist.

**This addon has been discontinued**

Rated 5 out of 5 stars (283)
718,950 users

1-Click YouTube Video Download

The simplest YouTube Video Downloader for all YouTube Flash sites, period.

Rated 4 out of 5 stars (489)
707,570 users

Download Flash and Video

Download Flash and Video is a great download helper tool that lets you download Flash games and Flash videos (YouTube, Facebook, Dailymotion, Google Videos and more) with a single click.
The downloader is very easy to use.

Rated 4 out of 5 stars (314)
678,727 users

Stylish

Restyle the web with Stylish, a user styles manager. Stylish lets you easily install themes and skins for Google, Facebook, YouTube, Orkut, and many, many other sites. You can even customize Firefox and other programs themselves.

Rated 4 out of 5 stars (747)
672,178 users

Flagfox No Restart

Displays a country flag depicting the location of the current website's server and provides a multitude of tools such as site safety checks, whois, translation, similar sites, validation, URL shortening, and more...

Rated 5 out of 5 stars (634)
602,492 users

Web Developer

The Web Developer extension adds various web developer tools to the browser.

Rated 5 out of 5 stars (216)
551,333 users

FireFTP

FireFTP is a free, secure, cross-platform FTP/SFTP client for Mozilla Firefox which provides easy and intuitive access to FTP/SFTP servers.

Check out my new project, FireSSH!

Rated 4 out of 5 stars (930)
547,301 users

LastPass Password Manager

LastPass, an award-winning password manager, saves your passwords and gives you secure access from every computer and mobile device.

Rated 4 out of 5 stars (1,227)
535,818 users

EPUBReader

With EPUBReader you can read ePub files just in Firefox. No additional software needed!

Rated 5 out of 5 stars (162)
429,774 users

Speed Dial

Direct access to your most visited websites

Rated 4 out of 5 stars (1,238)
413,741 users

User Agent Switcher

The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.

Rated 4 out of 5 stars (249)
367,507 users