Add-ons
Most Popular Extensions
Sort by:
Lightning
Requires Restart
Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.
ImportExportTools
Requires Restart
Adds some tools to import and export folders and messages
Provider for Google Calendar
Requires Restart
Allows bidirectional access to Google Calendar
Manually sort folders
Requires Restart
This extension allows you to manually sort (order) your folders in the folder pane of Thunderbird or automatically sort them, but in a better way. This extension also allows you to re-order accounts in the folder pane.
Enigmail
Featured
OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.
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
Quicktext
Requires Restart
Quicktext is an extension for Thunderbird that lets you create templates that can be easily inserted into your own emails.
gContactSync
Requires Restart
Synchronizes contacts & groups between Thunderbird and Google Contacts.
CompactHeader
Requires Restart
Featured
Add symbol in header plane to switch between compact and expanded view. Options to switch between one or two lines compact view, which buttons should be displayed in header pane. New beta version available from http://compactheader.mozdev.org/
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).
Send Later
Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
Signature Switch
Requires Restart
Switch the signature on/off or choose a new one from your predefined set.
Mail Merge
Requires Restart
Featured
Create and Save or Send Multiple Individual and Personalized Messages from a Draft
CardBook
Requires Restart
Featured
A new Thunderbird address book based on the CardDAV and vCard standards.
Twitter: @CardBookAddon
Mail Redirect
Featured
Allow to redirect (a.k.a. "remail") mail messages to other recipients.
Addressbooks Synchronizer
Requires Restart
Synchronizes selected addressbooks with other instances of thunderbird
using ftp/webdav/imap servers
Display Quota
Requires Restart
This extension will display the current status of your IMAP quota in thunderbird's statusbar and will warn you when you reach a configurable limit...
Stationery
Requires Restart
Extension to mimic Outlook Express Stationery.
Allow you to use HTML files as templates for mail. Also allow custom template in replies or forwarded mail!
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).
To create your own collections, you must have a Mozilla Add-ons account.
