Release Notes

Thunderbird Desktop

Version 91.2.0 | Released October 7, 2021

Check out the notes below for this version of Thunderbird. As always, you’re encouraged to tell us what you think, or file a bug in Bugzilla.

For more on all the new features in Thunderbird 91, see New in Thunderbird 91.0.

System Requirements: Details

  • Windows: Windows 7 or later
  • Mac: macOS 10.12 or later (macOS 11.0 for Silicon)
  • Linux: GTK+ 3.14 or higher

What’s Changed


Saving a single message as .eml now uses a unique filename

What’s Fixed


New mail notifications did not properly take subfolders into account


Decrypting binary attachments when using an external GnuPG configuration failed


Account name fields in the account manager were not big enough for long names


LDAP searches using an extensibleMatch filter returned no results


Read-only CalDAV calendars and CardDAV address books were not detected


Multipart messages containing a calendar invite did not display any of the human-readable alternatives


Some calendar days were displayed incorrectly or duplicated (eg. two "29th" days of a particular month)


Phantom event was shown at the end of each day in Calendar week view


Various security fixes

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