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Shrunked Image Resizer

Make your photos smaller, so they don't take forever to email.

Rated 3 out of 5 stars (38)
7,276 users

Dorando keyconfig Requires Restart

A modified Dorando's addon to rebind keyboard shortcuts. It is designed to be a drop-in replacement, keeping your old settings. (See details for upgrade instructions.)

As of version 2016.2, Custom keys (using custom JavaScript) work again!

Rated 5 out of 5 stars (47)
4,544 users

Open With

Open With can open your web links in any browser installed on your computer.

Not yet rated
1,156 users

Bluhell Firewall

Get a faster browsing experience by blocking nasty web resources using Bluhell Firewall, the lightweight Ad-Blocker and Tracking/Privacy Protector.

Rated 4 out of 5 stars (497)
1,132 users

Restart

"Restart" menu and button, with configurable shortcut key.

Rated 5 out of 5 stars (107)
542 users

UnMHT

UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.

Rated 4 out of 5 stars (300)
283 users

Silent Block

Minimum and fast URL blocker.

Rated 4 out of 5 stars (31)
208 users

No need flash plugin on embeded youtube movies

No need flash plugin on embeded youtube movies

Rated 4 out of 5 stars (25)
202 users

AutoSlide

The AutoSlide addon automatically moves the splitter between the thread and the message pane in Thundbird so that the thread pane is set to a optimal height.

Rated 5 out of 5 stars (2)
155 users

No Resource URI Leak

Deny resource:// access to Web content: We fill the hole to defend against fingerprinting. Very important to Firefox privacy. A direct workaround for bugzil.la/863246

Rated 4 out of 5 stars (31)
90 users

mozCleaner

Cleans your Firefox, Thunderbird, SeaMonkey, Fennec (unstable), Instantbird and BlueGriffon.

Rated 3 out of 5 stars (6)
79 users

WDownloader WGrabber

WDownloader plugin for Firefox

Rated 5 out of 5 stars (1)
71 users

URLFilter

Block advertisement and access to adult sites

Rated 4 out of 5 stars (23)
69 users

Extension Auto-Installer

Important note: This extension will not work in Firefox 57 and above. Providing this functionality in Firefox is no longer possible, the extension is discontinued.

Rated 5 out of 5 stars (48)
68 users

Remote XUL Manager

Manages the Remote XUL whitelist to allow websites and local files to load XUL content. For versions compatible with Firefox 41 and lower, see All Versions page below.

Rated 5 out of 5 stars (36)
52 users

InfoNotary Configurator for Mozilla Requires Restart

Configures Mozilla for work with certificates issued by InfoNotary Plc.

Rated 3 out of 5 stars (4)
49 users

Redirect Bypasser

Avoid redirects and has direct access to the sites you want to visit.

Rated 4 out of 5 stars (55)
39 users

Thunderbird Addons Test

Change prefs so that you use addons.thunderbird.net as the provider for add-on downloads and updates.

Not yet rated
31 users

Crash Me Now! (Simple)

Crash yourself with ease

Rated 5 out of 5 stars (2)
26 users

techblocker

Search with Joy! Block Ads While Surfing!

Rated 5 out of 5 stars (3)
26 users