Add-ons
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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.
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).
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.
MinimizeToTray revived
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 ...
Display Mail User Agent
Requires Restart
Displays icon for user agent of received mails.
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.
Highlighter
Requires Restart
Quickly highlight some text in Thunderbird message composing windows.
ThunderBirthDay
Requires Restart
Display birthdays from the Thunderbird addressbooks as events in Lightning.
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.
Join-NG
Requires Restart
Join partial messages. Somewhat similar to MS Outlook Express "combine and decode".
BiDi Mail UI
Requires Restart
Direction control and BiDi-related charset misdetection correction
Awesome Auto Archive
Automatically do Archive/Copy/Delete/Move actions based on user defined rules
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.
Folderpane Tools
Requires Restart
Allows for customization of the folder pane. Accounts can be rearranged and the startup folder can be chosen.
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!
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.
To create your own collections, you must have a Mozilla Add-ons account.
