Most Popular Extensions
Confirm E-mail address before sending mail
Uploads your large attachments to your Dropbox instead of sending them by email. This uses Thunderbird's FileLink feature.
Displays tabs which allows quick navigation between time periods in Lightning calendar. All views of calendar are supported. Color of tab texts can be adjusted.
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!
Add emojis to your e-mails.
Causes Thunderbird's main window to minimize instead of closing. You can still close Thunderbird through the menu.
Synchronizes selected addressbooks with other instances of thunderbird
using ftp/webdav/imap servers
Persistent sticky notes for Thunderbird associated to mails.
In TB 78, you can define the note position in the settings. If you have a large screen, you can even display the notes outside of TB's main window, so it won't hide anything.
Check the message contents and addresses before you send the message...
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.
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.
Automatically archives old mails (Improved version of the orginal Autoarchive Add-on)
Mailbox Alert allows you to specify, for each seperate mail folder, a message, sound and/or a system command that will be executed when new mail is found there. ...
Quickly generate mail filters on the fly, by dragging and dropping mails and analyzing their attributes. Create a filter in less than 10 seconds, it's as easy as: drag, click, click.
By popular demand, supports SORTING filters alphabetically.
Uploads your large attachments to your Box instead of sending them by email.
Add toolbar for toggling tags.
Adds many new mail filter actions - launch a file, suppress notification, remove star or tag, mark replied or unread, copy as "read", append text to subject.
DKIM Verifier Featured
Verifies the DKIM-Signature of an e-mail.
Upload large attachments to your Cloud and send the link by email
Make your photos smaller, so they don't take forever to email.