Top-Rated Extensions

Subscribe

YouTube High Definition

YouTube High Definition is a powerful tool that will let you automatically play all YouTube videos in HD (High Definition), turn off annotations, change video player size, auto stop videos, auto mute videos, control embedded videos and much more.

Rated 5 out of 5 stars (241)
642,377 users

Theme Font & Size Changer

Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.

Rated 5 out of 5 stars (181)
107,315 users

YouTube Flash Video Player

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

Rated 5 out of 5 stars (56)
269,536 users

QuickFolders (Tabbed Folders) Requires Restart

The "Swiss army knife" of folders. Turn your favorites into tabs - open folders and subfolders, move mails without scrolling around or searching. powerful + easy.

See new mail at a glance after automatic filtering - supports quickFilters addon!

Rated 5 out of 5 stars (117)
24,808 users

Messenger for Facebook™

Messenger for Facebook™ lets you bring a Messenger right into your browser to chat with your friends.

Rated 5 out of 5 stars (39)
25,205 users

Add-ons Manager Context Menu Requires Restart

Add more items to Add-ons Manager context menu.

Rated 5 out of 5 stars (37)
112,806 users

Classic Toolbar Buttons

'Classic Toolbar Buttons' add-on restores old toolbar button ui (known from Fx 4-7s small view, Fx 4-12s large view & Tb 5-14) for current Firefox, Thunderbird and Seamonkey versions.

Beta builds on versions page!

Rated 5 out of 5 stars (163)
38,026 users

Open With Photoshop

Open With Photoshop is a new companion for web and graphic designers to open up any web image with Adobe Photoshop via a single and quick mouse click.

Rated 5 out of 5 stars (72)
15,837 users

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 (5,030)
18,520,772 users

Reader

Reader is the ultimate Reader tool for Firefox.

Rated 5 out of 5 stars (65)
33,014 users

Decentraleyes

Protects you against tracking through "free", centralized, content delivery. It prevents a lot of requests from reaching networks like Google Hosted Libraries, and serves local files to keep sites from breaking. Complements regular content blockers.

Rated 5 out of 5 stars (90)
76,420 users

Extension Auto-Installer

Extension Auto-Installer is a helper for Firefox/SeaMonkey/Thunderbird extension developers: it allows automatically adding or updating browser extensions, e.g. via command line tools. This makes testing your changes easier.

Rated 5 out of 5 stars (21)
3,384 users

Slim Add-ons Manager

The Add-ons Manager slims down!
This add-on reduces the height of entries in the Add-on Manager, so you can display more of them at a time.

Rated 5 out of 5 stars (52)
8,653 users

Old Default Image Style

Restores the default image style used for top-level images in previous versions of Firefox.

Rated 5 out of 5 stars (97)
7,003 users

Webmaster SAPE Requires Restart

Toolbar contains a set of functions, which expands the abilities of webmasters and optimizers, when working in the interface of SAPE exchange.

Rated 5 out of 5 stars (168)
6,331 users

Go Parent Folder Requires Restart

Add "Go Parent Folder" menu to context menu in The Library list view and Search result in Bookmarks Sidebar.

Rated 5 out of 5 stars (113)
8,870 users

HTitle (discontinued) Requires Restart

Hide title bar if window is maximized.

[!] This add-on has been discontinued.

This extension created only for GNOME 3. It can create problems with another DE. However, you can use HTitle at your own risk (need enable "legacy" mode on settings).

Rated 5 out of 5 stars (119)
8,167 users

Download Status Bar

If you are the kind of person who likes to have total control over every aspect of your downloads, "Download Status Bar" is the add-on you are looking for.

Rated 5 out of 5 stars (343)
220,653 users

Stylish Sync

Sync engine for Stylish with backup / restore facility.

Rated 5 out of 5 stars (26)
5,522 users

Simple YouTube MP3 Button

Adds a small and simple button to YouTube videos that allows you to quickly download the audio of the video as an MP3 file (quality of the MP3 is as high as the video offers) without having to leave the page.

Rated 5 out of 5 stars (52)
41,184 users