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 (4,884)
21,925,243 users

Video DownloadHelper

The easy way to download and convert Web videos from hundreds of YouTube-like sites.

Rated 4 out of 5 stars (7,119)
4,897,708 users

Easy Screenshot Requires Restart

Capture a screenshot of the whole webpage, and save in your desktop in default.

Rated 4 out of 5 stars (110)
3,059,867 users

Firebug Featured

Firebug integrates with Firefox to put a wealth of development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page...

Rated 5 out of 5 stars (1,840)
2,455,828 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)
2,264,585 users

uBlock Origin Featured

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

Rated 5 out of 5 stars (686)
1,756,107 users

Ghostery Featured

Increase your browsing privacy, protection, and speed.

Rated 5 out of 5 stars (1,308)
1,502,238 users

DownThemAll! Featured

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

Rated 4 out of 5 stars (1,804)
1,345,867 users

Greasemonkey Requires Restart Featured

Customize the way a web page displays or behaves, by using small bits of JavaScript.

Rated 4 out of 5 stars (1,012)
1,325,491 users

Download YouTube Videos as MP4 Featured

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)
1,173,306 users

Flash Video Downloader - YouTube HD Download [4K] Requires Restart

Flash Video Downloader helps you download any video (flv, mp4, HD) from YouTube, Facebook, Break, Metacafe and more in one click. You can download mp3, music (iPod), avi and more. Download Flash games. Download Helper. 4K download.

Rated 4 out of 5 stars (701)
1,067,143 users

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

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)
963,347 users

Search and New Tab by Yahoo

This Add-on sets your default Search to Yahoo, and it brings a fresh look to every new tab page, powered by Yahoo.

Rated 3 out of 5 stars (19)
933,360 users

Tab Mix Plus Requires Restart Featured

Tab Mix Plus enhances Firefox's tab browsing capabilities. It includes such features as duplicating tabs, controlling tab focus, tab clicking options, undo closed tabs and windows, plus much more. It also includes a full-featured session manager.

Rated 4 out of 5 stars (2,620)
877,256 users

Google Translator for Firefox Requires Restart Featured

With this addon you can translate any text to your own language with one click or hot-key. You can either translate the selected text, this way the translated text will overwrite the original selected text, or you can translate the full page too.

Rated 4 out of 5 stars (354)
859,926 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)
857,963 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)
808,833 users

YouTube™ Video and Audio Downloader

Downloads YouTube videos in all available formats (FLV, MP4, WebM, and 3GP) with video quality of your choice. It also contains a pure JavaScript library to extract the ORIGINAL audio file embedded in video files.

Rated 4 out of 5 stars (355)
777,716 users

Yahoo Toolbar and New Tab

This Add-on gives you a simplified version of Yahoo Toolbar along with Flickr images on every new tab. It also provides quick access to your top sites.

Rated 2 out of 5 stars (384)
744,526 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)
727,163 users