Add-ons
Message Composition
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Color Text Compose Buttons
Requires Restart
Adds Text Color Buttons in Compose Toolbar and More: Pixel FontSize, Strikethough, Sub & Superscript, Lower & UpperCase. Also provide Tools: Insert iframe, Launch MathType, Maths & Greek Symbols, Load Template Variables and Duplicate Compose Window.
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).
ThunderAI (ChatGPT, Gemini, Ollama in your emails)
ThunderAI uses the capabilities of ChatGPT, Google Gemini, Anthropic or Ollama to enhance email management.
It enables users to analyze, write, correct, assign tags, create calendar events and tasks and optimize their emails.
CatchAll Bird
This extension improves the use of CatchAll-Addresses with Thunderbird.
It handles incoming messages addressed to all prefix@domain.tld for a fixed domain.
For each prefix the AddOn can create a new identity and folder.
CustomCSS
Allow the user to configure custom CSS that will be added to messages when edited
(new, reply and forward). The custom CSS will be added to a newly created <style>
element in the email's head.
Extra Format Buttons
Requires Restart
Adds a font size (in pixels), strikethough, subscript and superscript buttons to Thunderbird's Compose Window.
ReplyWithHeader
DL for Thunderbird
Requires Restart
Allows to convert large attachments to links automatically without 3rd party providers.
Automatic Dictionary
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.
SmartTemplates
Featured
SmartTemplates 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.
Identity Chooser
Identity Chooser helps you to always use the correct identity when composing a new email.
Reply To All Reminder
Requires Restart
Asks for confirmation when "Reply" instead of "Reply to All" is pressed on an email with multiple recipients.
EasyRight2Left
Requires Restart
Change direction from Left to Right and Right to Left for Persian, Arabic, Hebrew etc. This Thunderbird extension is based on ComposeRTF available in https://addons.thunderbird.net/en-US/thunderbird/addon/composertf/
Custom Sender Address and Reply
Requires Restart
Select sender mail address based on the recipient and reply with the same address
Expand mailing lists
Adds an 'expand lists' button to the compose window. It replaces all mailing lists with their contacts.
AutoCopy_rebirth
Requires Restart
Lightweight add-on that automatically copies any highlighted text to clipboard.
Simple Mail Redirection
Allows you to resend (also known as redirect) email messages.
Uses 'cardbook' if installed
Bases on the add-on 'Mail Redirect' by Onno Ekker and Pawel Krzesniak
Please see the support page on how to use and why it sometimes does not work!
Markdown Here Revival
A revival of the popular Markdown-Here addon for Thunderbird.
Markdown Here Revival is a Thunderbird extension that lets you write emails in Markdown and render them as HTML before sending.
Resubmit
SMTP Switch RebornTo create your own collections, you must have a Mozilla Add-ons account.
