Add-ons
Recently Updated Extensions
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ChatGPT Bulk Delete
Browser Extension to bulk delete and archive ChatGPT chats.
uBird
Finally, an efficient blocker, now for Thunderbird! Easy on CPU and memory.
MailCheck: Send Protection
MailCheck helps prevent accidental email leaks by checking recipient domains before sending. Can be configured to warn & allow users to deny when email messages include non-allowed domains or prohibited domains.
Owl for Exchange
Allows you to use your Exchange and Office365 email account with Thunderbird using Outlook Web Access (OWA).
BYO AI Grammar
Inline grammar suggestions while composing email. You bring your own LLM via an Open AI-compatible provider, including local LLM; tested with LM Studio on Ubuntu and together.ai Defaults to google/gemma-3n-E4B-it
ToneCraft
ToneCraft is a Thunderbird extension that detects (and blocks) unprofessional language in outgoing emails and suggests polite alternatives with AI.
It helps you maintain a courteous tone and avoid accidental rudeness.
Clippings for Thunderbird
Save frequently-entered text for pasting later.
CardBook
Featured
A new Thunderbird address book based on the CardDAV and vCard standards.
Twitter: @CardBookAddon
Image Preview
Image Preview is a Thunderbird extension that allows you to preview image attachments and embedded images from email messages in a convenient popup window.
Start with Inbox
Selects the latest message in the Inbox after start of Thunderbird.
Last selected message
The add-on remembers the last selected message in visited folders. After restarting Thunderbird, when we enter the previously visited folder, this message will be displayed, just like in Microsoft Outlook.
Failed Recipient Extractor [Bounce Mail]
Extracts unique recipient addresses from selected non-delivery reports and failed delivery notifications.
Auto Avatars
Automatically populates contact photos with their Libravatar or Gravatar photo. Includes support for custom instances and federation!
Calendar event from email with date detection
This plugin offers to create new events based on the email subject and content. It recognizes dates automatically
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.
WhatsApp Contacts Saver
Powerful extension to export contacts from WhatsApp Groups, Chats, and Business Labels.
Duplicate Contacts Manager
This Thunderbird add-on searches address book(s) for pairs of matching contact entries.
It can automatically delete entries that have equivalent or less information than the other one.
Any remaining matches are presented for manual treatment.
Unmangle Microsoft ATP Safelinks
Users of outlook.com and o365 who have Advanced Thread Protection enabled will have all URL's in emails changed to redirect them to an Microsoft filter before opening. This is a bad idea.
This plugin will change the URL back to the original value.
Mail Merge
Create and Save or Send Multiple Individual and Personalized Messages from a Draft
Unified Folders Debugging
An add-on to help debugging problems with the Unified Folders mode.
To create your own collections, you must have a Mozilla Add-ons account.
