Most Popular Extensions
Make your photos smaller, so they don't take forever to email.
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.)
Open With can open your web links in any browser installed on your computer.
Get a faster browsing experience by blocking nasty web resources using Bluhell Firewall, the lightweight Ad-Blocker and Tracking/Privacy Protector.
"Restart" menu and button, with configurable shortcut key.
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.
Minimum and fast URL blocker.
No need flash plugin on embeded youtube movies
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.
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
Cleans your Firefox, Thunderbird, SeaMonkey, Fennec (unstable), Instantbird and BlueGriffon.
WDownloader plugin for Firefox
Block advertisement and access to adult sites
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.
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.
InfoNotary Configurator for Mozilla Requires Restart
Configures Mozilla for work with certificates issued by InfoNotary Plc.
Avoid redirects and has direct access to the sites you want to visit.
Change prefs so that you use addons.thunderbird.net as the provider for add-on downloads and updates.
Crash yourself with ease
Search with Joy! Block Ads While Surfing!