Add-ons
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ImportExportTools NG
Adds tools to import/export messages and folders
EML, MBOX, HTML PDF , Plaintext Support and CSV support with indexes and file naming.
Provider for Google Calendar
LookOut (fix version)
LookOut decodes winmail.dat (TNEF encoded) files that may come from a misconfigured Microsoft Exchange server or Outlook user allowing access to the original attachments
Support: Thunderbird
Quicktext
Quicktext is an extension for Thunderbird that lets you create templates that can be easily inserted into your own emails.
Send Later
Remove Duplicate Messages
Search and remove messages which are the same as other messages in your mail folders (referred to as duplicates or dupes).
TbSync
TbSync is a central user interface to manage cloud accounts and synchronize their contact, task and calendar information with Thunderbird.
CardBook
Featured
A new Thunderbird address book based on the CardDAV and vCard standards.
Twitter: @CardBookAddon
Mail Merge
Create and Save or Send Multiple Individual and Personalized Messages from a Draft
Grammar and Spell Checker — LanguageTool
Check your emails for spelling and grammar issues
Signature Switch
Switch the signature on/off or choose a new one from your predefined set.
FileLink Provider for Dropbox
Uploads your large attachments to your Dropbox instead of sending them by email. This uses Thunderbird's FileLink feature.
Provider for CalDAV & CardDAV
This extension is no longer needed. Thunderbird has native CalDAV and CardDAV support.
Owl for Exchange
Allows you to use your Exchange and Office365 email account with Thunderbird using Outlook Web Access (OWA).
FileLink provider for WebDAV
Featured
Uploads your large attachments to your WebDAV account instead of sending them by email.
FileLink provider for Send
Securely encrypt and upload large attachments to any Send service instance (formerly Firefox Send).
Web Translate
Web Translate is easy to use translator for your Web browser / Thunderbird!
Minimize on Close
Causes Thunderbird's main window to minimize instead of closing. You can still close Thunderbird through the menu.
Textmarker
Highlights selected text when composing emails. Default colour is yellow - other colours are available via Options.
(Works only during writing an e-mail, i.e. only in the compose window.)
*cloud - FileLink for Nextcloud and ownCloud
Featured
Upload large attachments to your Cloud and send the link by email
To create your own collections, you must have a Mozilla Add-ons account.
