Release Notes

Thunderbird Desktop

Version 78.4.0 | Released October 21, 2020

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

For more on all of the new features in Thunderbird 78, see New in Thunderbird 78.0.

System Requirements: Details

  • Windows: Windows 7 or later
  • Mac: macOS 10.9 or later
  • Linux: GTK+ 3.14 or higher

What’s New

new

MailExtensions: browser.tabs.sendMessage API added

new

MailExtensions: messageDisplayScripts API added

What’s Changed

changed

Yahoo and AOL mail users using password authentication will be migrated to OAuth2

changed

MailExtensions: messageDisplay APIs extended to support multiple selected messages

changed

MailExtensions: compose.begin functions now support creating a message with attachments

What’s Fixed

fixed

Thunderbird could freeze when updating global search index

fixed

Multiple issues with handling of self-signed SSL certificates addressed

fixed

Recipient address fields in compose window could expand to fill all available space

fixed

Inserting emoji characters in message compose window caused unexpected behavior

fixed

Button to restore default folder icon color was not keyboard accessible

fixed

Various keyboard navigation fixes

fixed

Various color-related theme fixes

fixed

MailExtensions: Updating attachments with onBeforeSend.addListener() did not work

fixed

Various security fixes

Learn What’s Next

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