Up & Coming Extensions
Markdown Here Requires Restart
Write your email in Markdown, then make it pretty.
Google+ Tab Requires Restart
Google+ Tab for Thunderbird
Thunderbird Biff Requires Restart
This add-on provides a visual indicator of new Thunderbird mail availability in supported clients (Firefox, Sunbird) and Thunderbird itself. Note: you MUST install this add-on in BOTH Thunderbird and supported clients as there are both client AND ser...
QuickArchiver Requires Restart
Clean up your inbox! While moving a mail the first time, QuickArchiver remembers the destination folder and enables you to move further mails with a single click. You can apply rules by sender, recipient and subject.
Change your Personas theme on each browser load.
FlashGot Mass Downloader Requires Restart
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.
This 15KB restartless add-on will add a "File" -> "Restart" menu item and a ctrl/cmd + alt + r hotkey to restart Firefox or Seamonkey.
Exit Button Thunderbird Requires Restart
Adds a toolbar button to exit Thunderbird. Go to View menu, Toolbars, Customize... and drag the icon where you want...
Display Mail User Agent Requires Restart
Displays icon for user agent of received mails.
Contact Photos Requires Restart
Displays contact photos in the message header.
Execute JS Requires Restart
EditEmailSubject Requires Restart
This module allows you to change email subjects
Extension List Dumper Requires Restart
This extension adds a button ("Dump list") to the Add-ons window. When this button is pressed, a new window is opened with the list of installed extensions, themes or plugins...
Stylish Tools Requires Restart
Quicker access to several Stylish features through a toolbar button and/or keyboard shortcuts. Available for Firefox, Thunderbird, and SeaMonkey
AttachmentExtractor Requires Restart
Extracts all attachments from selected messages and then can delete, detach or mark-read.
InspectorWidget Requires Restart
Adds toolbar button and context menus for invoking the DOM Inspector (DOMi) for either chrome or content elements.
Folder Pane View Switcher Requires Restart
Add arrow buttons for rotating among folder views, and switch to "All Folders" view when hovering over the folder pane during drag & drop.
Select Address Book Text Requires Restart
Copy and paste a name, phone number, address or other text from your Thunderbird address book quickly, with just a single menu click.