Most Popular Extensions


Adblock Plus 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 (4,885)
19,962,079 users

Lightning Requires Restart 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 (1,922)
5,855,568 users

NoScript Security Suite Requires Restart 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 (1,581)
2,124,696 users

uBlock Origin

Finally, an efficient blocker. Easy on CPU and memory.

Rated 5 out of 5 stars (690)
1,678,414 users

DownThemAll! Featured

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

Rated 4 out of 5 stars (1,804)
1,224,868 users

Download YouTube Videos as MP4

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 (431)
1,062,438 users

Web of Trust, MyWOT/WOT: Website Reputation Rating Requires Restart

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 4 out of 5 stars (1,305)
877,227 users

FlashGot Mass Downloader Requires Restart 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 (535)
782,079 users

LastPass Password Manager Requires Restart

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 (1,393)
721,096 users

1-Click YouTube Video Download Requires Restart

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

Rated 4 out of 5 stars (540)
652,224 users

Download Flash and Video Requires Restart

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 (403)
631,762 users

Element Hiding Helper for Adblock Plus

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 (452)
584,171 users


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 (666)
483,639 users

Stylish Requires Restart

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

Rated 4 out of 5 stars (835)
448,796 users

Web Developer Requires Restart

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

Rated 5 out of 5 stars (249)
447,776 users

FireFTP Requires Restart

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 (972)
444,883 users

EPUBReader Requires Restart

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

Rated 5 out of 5 stars (178)
403,099 users

ImportExportTools Requires Restart

Adds some tools to import and export folders and messages

Rated 4 out of 5 stars (150)
374,853 users

S3.Google Translator Requires Restart

S3.Google Translator adds the power of Google Translate’s automatic translations to your browser!
It supports translation of selected text, entered phrase or whole webpage between any of 80+ languages.

New Feature: Language learning!

Rated 5 out of 5 stars (382)
373,176 users

Speed Dial Requires Restart

Direct access to your most visited websites

Rated 4 out of 5 stars (1,284)
349,051 users