Most Popular Extensions
Synchronizes selected addressbooks with other instances of thunderbird
using local files, webdav servers or imap servers
CompactHeader Requires Restart
Add symbol in header plane to switch between compact and expanded view. Work only for Thunderbird 68.0 and older. Currently, there are no plans to update this for newer versions.
Adds the Google Calendar web interface in a new Thunderbird tab. Creating and viewing events works like in a browser (Firefox, Chrome, ...)
Add emojis to your e-mails.
Upload large attachments to your Cloud and send the link by email
Confirm E-mail address before sending mail
DOM Inspector Requires Restart
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
Persistent sticky notes for Thunderbird associated to mails. You can email them/print/copy to clipboard.
If you have a large screen, you can even display the notes outside of TB's main window, so it won't hide anything.
The best Translator for Thunderbird!
Check the message contents and addresses before you send the message...
ImportExportTools Requires Restart
Adds some tools to import and export folders and messages
Check your emails for spelling and grammar issues
The "Swiss army knife" of folders. Turn your favorites into tabs - open folders and subfolders, move mails without scrolling around or searching. powerful + easy.
See new mail at a glance after automatic filtering - supports quickFilters addon!
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.
Automatically archives old mails (Improved version of the orginal Autoarchive Add-on)
Securely encrypt and upload large attachments to any Send service instance (formerly Firefox Send).
Add toolbar for toggling tags.
Uploads your large attachments to your Box instead of sending them by email.
Add simple functions to report spams or phishing to Signal Spam by one click.
The add-on will also alert you if you open a fraudulent e-mail (phishing).
Phoenity icons for Thunderbird