Recently Updated Extensions
ImportExportTools Requires Restart
Adds some tools to import and export folders and messages
Identity Chooser Requires Restart
Identity Chooser helps you to always use the correct identity when composing a new email.
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.
This extension makes browsing for extensions easier at addons.mozilla.org. It fixes incorrect information about some extensions being not available for SeaMonkey and adds links to the Add-on Converter where needed.
Nostalgy Requires Restart
Keyboard shortcuts to change folder, move/copy messages, with folder name auto-completion.
Enhanced Priority Display Requires Restart
Enhanced thread pane display of message priorities.
Decide whether to allow or block remote content in messages by comparing the names of the folders in which they are located to configured regular expressions.
Add menu commands for replying to multiple messages at the same time.
Adds icons to buttons and/or menus.
Keep your menus in check by filtering out items you never use.
This extension is not being converted to a WebExtension.
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
Contact Photos Requires Restart
Displays contact photos in the message header.
gContactSync Requires Restart
Synchronizes contacts & groups between Thunderbird or SeaMonkey and Google Contacts. Imports Facebook friends, contacts you follow on Twitter, and more.
GNOMErunner Options Requires Restart
Allows to customize GNOMErunner theme
Caret Out Requires Restart
Disables change of the caret browse mode by shortcut key(F7).
Saved Password Editor Requires Restart
Adds the ability to create and edit entries in the password manager.
DownloadStudio Firefox Integration Requires Restart
Firefox Integration for DownloadStudio
Makes every page to have light text on dark background (exact colors are customizable)
Firefox version is here: https://addons.mozilla.org/firefox/addon/dark-background-light-text/
Mouse Gestures Suite Requires Restart
Mouse gestures for SeaMonkey & Firefox: navigate & execute commands using mouse gestures (with single mouse button) and rocker gestures (by pressing 2 mouse buttons). Also: scroll wheel navigation, page scrolling, tab scrolling.
Be in control of which cross-site requests are allowed. Improve the privacy of your browsing by not letting other sites know your browsing habits. Secure yourself from Cross-Site Request Forgery (CSRF) and other attacks.