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Web Developer

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

Rated 5 out of 5 stars (178)
775,513 users

Personas Plus

Personas are free, easy-to-install "skins" for Firefox. Personas Plus extends that built-in functionality to give you even more control and easier access to new, popular, and your own favorite Personas.

Rated 3 out of 5 stars (876)
771,106 users

IE Tab V2 (Enhanced IE Tab)

Note: If you are encountering the Connecting... problem see instructions below.

The updated, fully supported IE Tab. Embed IE in a Firefox tab. IE Tab Features: FF 4+ support, IE 7-9 compatibility modes, old IE Tab settings import.

Rated 4 out of 5 stars (376)
730,279 users

Stylish Featured

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 (598)
704,423 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 (64)
696,606 users

Google Translator for Firefox 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 (227)
687,014 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 5 out of 5 stars (213)
669,012 users

BetterPrivacy Featured

Remove or manage a new and uncommon kind of cookies, better known as LSO's.The BetterPrivacy safeguard offers various ways to handle Flash-cookies set by Google, YouTube, Ebay and others...

Latest updates: See bottom link 'version history'!

Rated 5 out of 5 stars (383)
650,176 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 or bribes...

Rated 5 out of 5 stars (162)
597,171 users

Speed Dial

Direct access to your most visited websites

Rated 4 out of 5 stars (1,095)
555,772 users

ImTranslator - Google, Microsoft Translator, TTS Featured

ImTranslator provides access to the online translation powered by Google Translate, Microsoft, Babylon for 66 languages. It includes dictionary, text-to-speech, back translation.
Complete Video Tutorial: http://youtu.be/UwK6529XZIQ

Rated 4 out of 5 stars (373)
523,918 users

Youtube Video and Audio Downloader No Restart Featured

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 out of FLV videos. It optionally downloads subtitles as well!

Rated 4 out of 5 stars (120)
508,981 users

Ant Video Downloader and Player

With the Ant.com Video Downloader, you can download video from Youtube or any other streaming site. Rare are the sites you will not be able to download from. We have integrated a flash video player too, so that you can play your files immediately.

Rated 4 out of 5 stars (373)
500,337 users

Xmarks Sync

Xmarks is the #1 bookmarking and open tab add-on. Keep your bookmarks, and open tabs backed up and synchronized across computers and browsers. Mobile phones with Premium access. Utilize LastPass to sync passwords!

Rated 4 out of 5 stars (2,320)
491,654 users

anonymoX

Easy anonymous web browsing.
– Change your IP-Address and country
– Visit blocked or censored websites.
– Delete cookies, show your public ip, and more

No proxies or other programs required

Rated 4 out of 5 stars (131)
487,765 users

EPUBReader Featured

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

Rated 5 out of 5 stars (129)
473,248 users

Lightbeam for Firefox No Restart Featured

Lightbeam is a Firefox add-on that enables you to see the first and third party sites you interact with on the Web. Using interactive visualizations, Lightbeam shows you the relationships between these third parties and the sites you visit.

Rated 3 out of 5 stars (303)
472,011 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 (195)
457,635 users

IE Tab

IE Tab - an extension from Taiwan, features: Embedding Internet Explorer in tabs of Mozilla/Firefox...

Rated 4 out of 5 stars (1,181)
455,552 users

DoNotTrackMe: Online Privacy Protection Featured

Protect your privacy. Stop companies and advertisers from tracking your browsing and sending you spam email.

Rated 4 out of 5 stars (324)
453,297 users