Download Mozilla Thunderbird 91.2.1

The Mozilla Foundation has released version 91.2.1 of Thunderbird. Thunderbird is an open source client for e-mail and newsgroups, with features such as support for various mail and news accounts, a spam filter, spell checker, and a customizable appearance. In version 91 has included a warning when an email is sent to a possibly non-existent address, or when there are too many addresses in the public address line. There is also support for CardDAV and a native client for a Mac equipped with an Apple Silicon processor.

At the moment it is not yet possible to do an automatic update from version 78 to 91. Manually downloading and running the installation file can update an existing installation. This automatic migration will be added in a future version. The following changes and improvements have also been made in this release:

What’s New

• Preference added to disable automatic pausing RSS feed updates after a fetch failure

Fixes

• Recipeint address pills in an error state could incorrectly merge with mailing list pills when expanding the list
• BCC-only messages could not be sent from the Outbox
• Default DSN request was not set when using “Edit as New Message”
• Vertical scrollbar in “Conversations” chat panel did not work correctly
• Chat account “Advanced Options” dialog had no clickable buttons on macOS
• RSS feed attachments could not be saved
• Public ICS calendars served with an incorrect Content-Type could not be added
• Setting a CalDAV calendar to manually update had no effect
• CalDAV calendars set to read-only became writable after restarting Thunderbird
• Saving a copy of a calendar invite (More -> Save As Copy) did not work
• Events in the first or last week of a month were not always printed when printing a month view
• accessibility improvements; clearer display of area of ​​focus
• Various theme improvements, HiDPI improvements
• “Attachments” menu panels for attached files were empty
• Stability improvements