Up & Coming Extensions
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.
Send Later Button Requires Restart
A simple button to invoke the (already existing) send later functions.
SyncKolab Requires Restart
SyncKolab can synchronize your calendar, address book and tasks against an IMAP server in Kolab formats version 1 (vCard/iCal) or version 2 (XML) or turn your Thunderbird/Lightning into a native Kolab Client (http://kolab.org).
Highlighter Requires Restart
Quickly highlight some text in Thunderbird message composing windows.
Smiley Fixer Requires Restart
Fixes Wingding Smileys in Outlook-generated emails
ImportExportTools Requires Restart
Adds some tools to import and export folders and messages
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.
Enhanced Priority Display Requires Restart
Enhanced thread pane display of message priorities.
Copy Sent to Current Requires Restart
Allows to place a copy of sent messages (aka FCC) into the currently active folder or any other folder you choose, when you create the message. Usually the copies are placed into the 'Sent' folder. For replies, you may also move the original message.
Contact Photos Requires Restart
Displays contact photos in the message header.
ConfigDate Requires Restart
ConfigDate allows to configure the "Date" column in message threadpane. When displaying the message header, it is possible to display the (default) formated date or the senders local sent time (Date-String).
Mail Merge Requires Restart
Mass Mail and Personal Mail
Send Later Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
Personal Level Indicators Requires Restart
Shows an indicator so you can tell if an email was addressed only to you (»), a group (›), or a mailing list.
ThreadKey Requires Restart
Strike the 'T' key to sort messages by thread, strike the 'U' key to sort them unthreaded again, just like the 'G' key switches to Grouped By Sort view
Lightning Nightly Updater (Unofficial) Requires Restart
Quickly get to the latest nightly build of Lightning relevant to the version of Thunderbird and the OS you're on.
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.
New Mail Attention Requires Restart
This addon calls attention to main window on new message arrival.
Dictionary Switcher Requires Restart
Toggles dictionaries automatically or manually and displays the currently selected one