Thunderbird

Thunderbird is a free, open-source, cross-platform application for managing email and news feeds. It is a local (rather than a web-based) email application that is powerful yet easy-to-use. Thunderbird is developed, tested, translated and supported by the folks at Mozilla Corporation and by a group of dedicated volunteers. Thunderbird gives you control and ownership over your email. There are lots of add-ons available for Thunderbird that enable you to extend and customize your email experience.

Thunderbird gives you IMAP/POP support, a built-in RSS reader, support for HTML mail, powerful quick search, saved search folders, advanced message filtering, message grouping, labels, return receipts, smart address book LDAP address completion, import tools, and the ability to manage multiple e-mail and newsgroup accounts.

Changes in Thunderbird 91.1.2:

  • Thunderbird will now warn if an S/MIME encrypted message includes BCC recipients

Fixes

  • Message Security popup did not display all recipients due a missing scrollbar
  • Delivery Status Notifications were only shown for the first recipient
  • Composing a message from a template with attachments failed due to a temporary file being removed
  • Attachment sizes were no longer included on printed emails
  • A message sent with multiple attachments sometimes only sent one
  • Thunderbird sometimes attached the wrong messages when forwarding multiple messages by attachment
  • Thunderbird did not re-prompt for an SMTP username if one was not provided
  • Messages with BCC recipients that were held in the Outbox did not retain the BCC header when moved to the Sent folder
  • Thunderbird displayed reminders for events that were cancelled or declined
  • New Feed Account dialog did not honor dark mode

Download: Thunderbird 91.1.2 for Windows (EN/US) | 64-bit | ~50.0 MB (Open Source)
Download: Thunderbird 91.1.2 for Linux (EN/US) | 65.2 MB
Download: Thunderbird 91.1.2 for Mac OS (EN/US) | 119.0 MB
Download: Thunderbird 91.1.2 in other languages
View: Thunderbird Website | Release Notes | Screenshot