A free email application from Mozilla that's easy to set up and customize

Thunderbird for Mac

Thunderbird 91.4.0

  -  119 MB  -  Open Source

Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of Thunderbird 91.4.0.


For those interested in downloading the most recent release of Thunderbird for Mac or reading our review, simply click here.


All old versions distributed on our website are completely virus-free and available for download at no cost.


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  • Thunderbird 91.4.0 Screenshots

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    Thunderbird 91.4.0 Screenshot 1
  • Thunderbird 91.4.0 Screenshot 2
  • Thunderbird 91.4.0 Screenshot 3
  • Thunderbird 91.4.0 Screenshot 4
  • Thunderbird 91.4.0 Screenshot 5

What's new in this version:

Fixed:
- IMAP startup performance improved for accounts with a multitude of folders
- Thunderbird failed to send messages when configured to use an IPv6 SMTP server by IP address (instead of a hostname)
- Forwarding messages with attachments sometimes failed
- Printing multiple messages at once was not possible
- Non-utf8 news groups were not supported
- Thunderbird stalled after sending a message with NNTP and SMTP recipients
- Using Thunderbird with multiple language packs caused high RAM and CPU use and sluggish performance
- Clicking a "mailto:" started the composer with the default sending identity instead of a configured alternate
- Drag and dropped text into a plain text message in the compose window was handled inconsistently
- FileLink messages did not display correctly when viewed in Outlook
- In account setup, after selecting an extension provided protocol, it was not possible to create an IMAP/POP account
- Multiday selections were not cleared when changing week viewed
- When creating a new event by clicking and dragging the mouse to create a box, the view did not auto-scroll after reaching the bottom
- Calendar Invitation Panel did not scroll when multiple invitations were pending
- Calendar print dialog did not have a cancel button
- Various security fixes