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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 (4,863)
20,733,488 users

Video DownloadHelper No Restart

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

Rated 4 out of 5 stars (5,314)
5,145,499 users

Firebug No Restart

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 (1,766)
2,375,734 users

Microsoft .NET Framework Assistant

Adds ClickOnce support and the ability to report installed .NET versions to the web server.

Rated 2 out of 5 stars (118)
2,252,595 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 (1,475)
2,161,664 users

DownThemAll! Featured

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

Rated 5 out of 5 stars (1,570)
1,415,646 users

Ghostery No Restart Featured

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

Rated 5 out of 5 stars (1,137)
1,400,269 users

Greasemonkey Featured

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

Rated 4 out of 5 stars (947)
1,314,812 users

Adblock Plus Pop-up Addon Featured

Adblock Plus Pop-up Addon extends the blocking functionality of Adblock Plus to those annoying pop-up windows that open on mouse clicks and other user actions.

Rated 5 out of 5 stars (173)
1,237,226 users

Flash Video Downloader - YouTube HD Download [4K]

Flash Video Downloader helps you to download any video (flv, mp4, HD) from YouTube-like, 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 (535)
1,174,469 users

Web of Trust - WOT Featured

Find out which websites you can trust. WOT adds intuitive traffic light-style icons next to search results and URLs to help you make informed decisions about whether to visit a site or not.

Rated 3 out of 5 stars (1,588)
1,109,659 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 (485)
1,022,290 users

Download YouTube Videos as MP4 No Restart 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 (335)
987,279 users

Tab Mix Plus 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 (2,493)
949,862 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 (439)
807,292 users

Flashblock

Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on...

Rated 4 out of 5 stars (1,142)
784,529 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 will be discontinued on June 2015**

Rated 5 out of 5 stars (264)
773,941 users

Google Translator for Firefox

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 (299)
756,338 users

Test Pilot

Help us make Firefox better by joining our structured user studies! No need to download this add-on if you are running Firefox 4 beta, - you are already a part of the team!

Rated 4 out of 5 stars (71)
754,948 users

1-Click YouTube Video Download

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

Rated 4 out of 5 stars (482)
736,032 users