Add-ons
Most Popular Extensions
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ImportExportTools
Requires Restart
Adds some tools to import and export folders and messages
Remove Duplicate Messages (Alternate)
Requires Restart
Search and remove messages which are the same as other messages in your mail folders (referred to as duplicates or dupes).
DOM Inspector
Requires Restart
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
ChatZilla
Requires Restart
A clean, easy to use and highly extensible Internet Relay Chat (IRC) client.
MinimizeToTray Reanimated
Requires Restart
MinimizeToTray Reanimated is an application mainly dedicated to Thunderbird to allow its minimization in the systray in one click. It is the update of MinimizeToTray Revived, which is not maintained anymore since the recent versions of Thunderbird.
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).
Display Mail User Agent
Requires Restart
Displays icon for user agent of received mails.
JavaScript Debugger
Requires Restart
As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.
Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.
FireTray
Requires Restart
A system tray extension for Linux and Windows, allowing to set up custom icon, hiding to tray instead of closing, display the number of unread messages in mailing applications, and other features ...
MinimizeToTray revived
Theme Font & Size Changer for ThunderBird
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.
Highlighter
Requires Restart
Quickly highlight some text in Thunderbird message composing windows.
FiltaQuilla
Requires Restart
Adds many new mail filter actions - launch a file, suppress notification, remove star or tag, mark replied or unread, copy as "read", append text to subject.
ThunderBirthDay
Requires Restart
Display birthdays from the Thunderbird addressbooks as events in Lightning.
Awesome Auto Archive
Automatically do Archive/Copy/Delete/Move actions based on user defined rules
P7MON
Nostalgy
Requires Restart
Keyboard shortcuts to change folder, move/copy messages, with folder name auto-completion.
Toolbar Buttons
Adds toolbar buttons to the customize toolbar window in several programs including Firefox, Thunderbird and SeaMonkey. Some of the buttons make commonly preformed actions quicker, others add new functionality.
Header Tools Lite
Requires Restart
Allows to modify the header and the source of messages
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!
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