Add-ons
Message Composition
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Send Later
Requires Restart
Featured
True "Send Later" functionality to schedule the time for sending an email.
Signature Switch
Requires Restart
Featured
Switch the signature on/off or choose a new one from your predefined set.
Mail Merge
Requires Restart
Create and Save or Send Multiple Individual and Personalized Messages from a Draft
Owl for Exchange
Allows you to use your Exchange email accounts that use Outlook Web Access (OWA) with Thunderbird
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!
ThunderPEC
Requires Restart
ThunderPEC semplifica la gestione della Posta Elettronica Certificata (PEC) e delle comunicazioni PCT e FatturaPA in Thunderbird.
Flex Confirm Mail
Requires Restart
Confirm mail address and attachments based on flexible rules.
Check and Send
Requires Restart
Check the message contents and addresses before you send the message...
Emoji
Auto Resize Image
Requires Restart
Resizer for inline and attachment images (JPEG, PNG, BMP and GIF image formats).
All platforms are supported (Windows, Linux and Macintosh).
SmartTemplate4
Requires Restart
SmartTemplate⁴ offers an easy and powerful way to automatically create customized replies by auto-inserting various mail headers. Templates can be created for every mail identity, Stationery files can now be imported and used directly.
Highlighter
Requires Restart
Quickly highlight some text in Thunderbird message composing windows.
Send Later Button
Requires Restart
Featured
A simple button to invoke the (already existing) send later functions.
Shrunked Image Resizer
Requires Restart
Make your photos smaller, so they don't take forever to email.
ThunderHTMLedit
Requires Restart
Featured
Thunderbird HTML editor. This add-on adds a HTML tab to the composition window where you can see and edit the HTML source of the message.
Grammar Checker
ReplyWithHeader
Requires Restart
Outlook style headers and few goodies for Thunderbird & Postbox.
Automatic Dictionary
Requires Restart
Remembers the language you use with a person or group of people, and switches the spellchecker language automatically for you next time. You do not have to do it manually any more. It remembers and switches it for you.
CategoryManager
Requires Restart
Category manager for Thunderbird contacts, also allows to send an email to all members of a category (categories can be used as contact groups).
Nextcloud for Filelink
Requires Restart
"Nextcloud for Filelink" is an Open Source Thunderbird extension which makes it easy to send large attachments with Thunderbird by uploading them first to a Nextcloud server and by then inserting the link into the body of your email.
To create your own collections, you must have a Mozilla Add-ons account.
