Recently Updated Extensions
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!
Year view Requires Restart
Year view for calendar.
Display Mail User Agent Requires Restart
Displays icon for user agent of received mails.
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
quickFilters Requires Restart
Quickly generate mail filters on the fly, by dragging and dropping mails and analyzing their attributes. Create a filter in less than 10 seconds, it's as easy as: drag, click, click.
By popular demand, supports SORTING filters alphabetically.
Send Later Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
Mailbox Alert Requires Restart
Mailbox Alert allows you to specify, for each seperate mail folder, a message, sound and/or a system command that will be executed when new mail is found there. ...
Automatically do Archive/Copy/Delete/Move actions based on user defined rules
Nostalgy Requires Restart
Keyboard shortcuts to change folder, move/copy messages, with folder name auto-completion.
DOM Inspector Plus! [dm] Requires Restart
Improved DOM Inspector! [dm version]. Box Model new layout & more data, see screenshot!. Horizontal scroll for Dom-Tree, and some more.
Inspects the structure and properties of a window and its contents.
QuoteCollapse Requires Restart
Collapse and expand quotes. Please see the extension homepage for further information.
Note that MozDev has shut down long ago (mailing list etc). Add-On homepage, source code and issue tracker are on GitHub, as linked on this page.
Provider for Google Calendar Requires Restart
Allows bidirectional access to Google Calendar
Identity Chooser Requires Restart
Identity Chooser helps you to always use the correct identity when composing a new email.
Thunderbird Integration for JIRA Requires Restart
This is a plugin for Thunderbird 3.3+ which is able to create Atlassian Jira issues out of e-mails or add the content of an e-mail as a comment on an Jira issue.
It is not yet ready to be used in Thunderbird 60.x.
AVIM Requires Restart
Vietnamese-language input method editor (IME). Type diacritics directly into any Web page, Web app, or dialog box. Convenient, comprehensive, secure.
Bộ gõ tiếng Việt cho phép đặt dấu trực tiếp vào bất kỳ trang Web, ứng dụng Web, hộp thoại.
Scans hyperlinks in composed messages and alerts if one of the hyperlinks is broken.
LookOut (fix version) 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).
Support: Thunderbird and SeaMonkey
Flexible Identity Requires Restart
Selects an identity based on the recipients list when sending an email
OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.