Add-ons
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Lightning
Requires Restart
Featured
Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.
DownThemAll!
Featured
The first and only download manager/accelerator built inside Firefox!
ImportExportTools
Requires Restart
Adds some tools to import and export folders and messages
Provider for Google Calendar
Requires Restart
Allows bidirectional access to Google Calendar
FlashGot Mass Downloader
Requires Restart
Featured
Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.
FireFTP
Requires Restart
FireFTP is a free, secure, cross-platform FTP/SFTP client for Waterfox which provides easy and intuitive access to FTP/SFTP servers.
Check out my new project, FireSSH!
Element Hiding Helper for Adblock Plus
Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
Session Manager
Session Manager saves and restores the state of all or some windows - either when you want it or automatically at startup and after crashes. It can also automatically save the state of open windows individually.
LookOut
Requires Restart
LookOut is a plugin which allows Thunderbird to interface with Microsoft's mail tools by decoding metadata and attachments encapsulated/embedded in a TNEF encoded attachment (aka winmail.dat).
Enigmail
Featured
OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.
User Agent Switcher
Requires Restart
The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.
Speed Dial
MinimizeToTray revived
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.
Menu Wizard
Requires Restart
Customize menus : Helps removing, moving and renaming menus and menu items
Colorize important menu for ease of use! (use Style (CSS))
Change or disable any of used keyboard shortcuts
Support: Firefox, Thunderbird and SeaMonkey
NetVideoHunter
Requires Restart
This add-on is a downloader that lets you easily download videos from sites like Youtube, Facebook, Metacafe, Dailymotion, Break, VKontakte and music for example from SoundCloud, Grooveshark and from many other sites...
SQLite Manager
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.
gContactSync
Requires Restart
Synchronizes contacts & groups between Thunderbird or SeaMonkey and Google Contacts. Imports Facebook friends, contacts you follow on Twitter, and more.
Send Later
Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
To create your own collections, you must have a Mozilla Add-ons account.
