Add-ons
Message Composition
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Send Later
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.
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.)
FileLink provider for Send
Securely encrypt and upload large attachments to any Send service instance (formerly Firefox Send).
FileLink Provider for Dropbox
Uploads your large attachments to your Dropbox instead of sending them by email. This uses Thunderbird's FileLink feature.
Owl for Exchange
Allows you to use your Exchange and Office365 email account with Thunderbird using Outlook Web Access (OWA).
*cloud - FileLink for Nextcloud OpenCloud ownCloud
Featured
Upload large attachments to your Cloud and send the link by email
Emoji
ThunderAI (ChatGPT, Gemini, Claude, Ollama)
ThunderAI uses the capabilities of ChatGPT, Google Gemini, Claude or Ollama to enhance email management.
It enables users to analyze, write, correct, assign tags, create calendar events and tasks and optimize their emails.
ReplyWithHeader
Shrunked Image Resizer
FileLink Provider for Box
Uploads your large attachments to your Box instead of sending them by email.
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!
BorderColors D
Shows a colorful border around the "New Message" window, so you can tell different identities apart.
Builds on the original BorderColors and the "GT" version, adding different border styles.
FEX.net FileLink
Easily upload large attachments anonymously to FEX.net using the cloudFile API — fast, secure, and hassle-free.
✨ Awesome Emoji Picker ✨
Modern, nice emoji picker that you can use to find and select emojis. It will be copied to your clipboard or even directly inserted into the e-mail, when you click on it.
You will certainly like it.
Identity Chooser
Identity Chooser helps you to always use the correct identity when composing a new email.
To create your own collections, you must have a Mozilla Add-ons account.
