Thunderbird 78.4 is out with these changes

The team behind the Thunderbird email app has released version 78.4. This is a maintenance release with a number of important fixes and extension improvements

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Thunderbird is my preferred email client of choice. I use this app on every PC and on every operating system I use. It is stable, contains all the features you need, supports add-ons and also comes with a useful RSS reader. I am using Thunderbird for many years and never felt the need to look for an alternative.

Thunderbird 78 doesn't support classic XUL add-ons any more, but includes some of their features natively. E.g. on Windows you can minimize the app to the system tray.

The following changes have been made in versions 78.4.

Thunderbird 78.3.3 changes

New features

  • MailExtensions: browser.tabs.sendMessage API added
  • MailExtensions: messageDisplayScripts API added


  • Yahoo and AOL mail users using password authentication will be migrated to OAuth2
  • MailExtensions: messageDisplay APIs extended to support multiple selected messages
  • MailExtensions: compose.begin functions now support creating a message with attachments


  • Thunderbird could freeze when updating global search index
  • Multiple issues with handling of self-signed SSL certificates addressed
  • Recipient address fields in compose window could expand to fill all available space
  • Inserting emoji characters in message compose window caused unexpected behavior
  • Button to restore default folder icon color was not keyboard accessible
  • Various keyboard navigation fixes
  • Various color-related theme fixes
  • MailExtensions: Updating attachments with onBeforeSend.addListener() did not work
  • Various security fixes

There are no known issues in this releases, things has got completely sorted.

Download Thunderbird

Download Thunderbird

The release notes are available here.

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Author: Sergey Tkachenko

Sergey Tkachenko is a software developer who started Winaero back in 2011. On this blog, Sergey is writing about everything connected to Microsoft, Windows and popular software. Follow him on Telegram, Twitter, and YouTube.

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