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YouTube Video Download & Convert Compatible with Firefox 57+

YouTube Video Download and Convert is the powerful add-on that lets you collect all media information available on YouTube. Advanced power panel lets you download, preview, play with and convert all media right inside Firefox.

Rated 4 out of 5 stars (32)
48,222 users

Turn Off the Lights Compatible with Firefox 57+

The entire page will be fading to dark, so you can watch the video as if you were in the cinema.

Rated 5 out of 5 stars (299)
46,964 users

YouTube™ Flash-HTML5 Compatible with Firefox 57+

Play YouTube™ Videos in Flash or HTML5 Player

Rated 4 out of 5 stars (64)
46,854 users

X-notifier (for Gmail,Hotmail,Yahoo,AOL ...) Compatible with Firefox 57+

Notifier for gmail, yahoo, hotmail, aol and more webmails.
X-notifier(aka WebMail Notifier) checks your webmail accounts and notifies the number of unread emails...
Supports : gmail, yahoo, hotmail, POP3/IMAP, facebook, twitter and more

Rated 4 out of 5 stars (1,743)
46,382 users

Exif Viewer Compatible with Firefox 57+

Displays the Exif and IPTC data in local and remote JPEG images.

Rated 4 out of 5 stars (90)
42,978 users

Lightshot (screenshot tool) Compatible with Firefox 57+

Easy and convenient screenshot tool. Allows you to make screenshots of any selected area (video and flash too), edit and upload it to server.

Rated 5 out of 5 stars (188)
42,489 users

Download with Internet Download Manager Compatible with Firefox 57+

when activated, interrupts the built-in download manager to direct links to IDMan (Internet Download Manager)

Rated 4 out of 5 stars (181)
42,127 users

ProCon Latte Content Filter

Block sites containing pornography, or any other kind of material, based on simple keyword lists.

Rated 4 out of 5 stars (259)
41,914 users

Native HLS Compatible with Firefox 57+

A new options button
Can now play embedded video if they are in the page
hls.js version can be selected in the options

Rated 3 out of 5 stars (5)
41,790 users

uMatrix Compatible with Firefox 57+

Point & click to forbid/allow any class of requests made by your browser. Use it to block scripts, iframes, ads, facebook, etc.

Rated 5 out of 5 stars (159)
40,417 users

The Camelizer - Price Tracker Compatible with Firefox 57+

Add price history charts and price watch features to Firefox when viewing product pages on Amazon. Use it to make informed purchasing decisions and to receive price drop alerts via email, Twitter, or RSS feed.

Rated 4 out of 5 stars (98)
39,940 users

OneNote Web Clipper Compatible with Firefox 57+

Save anything on the web to OneNote. Clip it to OneNote, organize and edit it, then access it from any device.

Rated 5 out of 5 stars (485)
37,842 users

Dark Background and Light Text

Makes every page (or only pages that you want) to have light text on dark background. Exact colors are customizable.

Rated 5 out of 5 stars (283)
37,760 users

PDF Mage Compatible with Firefox 57+

Save any page as PDF

Rated 4 out of 5 stars (82)
34,771 users

SeoQuake SEO extension Compatible with Firefox 57+

Accelerate your SEO efforts on the fly. SEOquake is a free plugin for browsers that provides you with key SEO metrics for a specific page, along with other useful tools such as SEO Audit and many others.

Rated 4 out of 5 stars (222)
34,536 users

Flash Video Player for Facebook™ Compatible with Firefox 57+

Flash Video Player for Facebook™ is a powerful tool that will let you choose Flash video player as default Facebook video player.

Rated 5 out of 5 stars (22)
34,488 users

AdBlocker Lite Compatible with Firefox 57+

block ads seamlessly on popular websites

Rated 5 out of 5 stars (28)
34,028 users

Html Validator Compatible with Firefox 57+

HTML Validator is a Mozilla extension that adds HTML validation inside Firefox and Mozilla. The number of errors of a HTML page is seen on the form of an icon

Until Firefox 56, use 0.974 (other versions)
For Firefox 57, see Web Extensions below

Rated 4 out of 5 stars (207)
32,258 users

HTTP/2 Indicator Compatible with Firefox 57+

An indicator showing HTTP/2 support in the address bar.

Rated 4 out of 5 stars (29)
30,275 users