Software update: Mozilla Thunderbird 78.5.1

The Mozilla Foundation has released version 78.5.1 of Thunderbird. Thunderbird is an open source email and newsgroup client, with features such as support for various mail and news accounts, a spam filter, spell checker and a customizable appearance. In version 78 , among other things, a dark mode has been added and other parts of the interface, such as the icons and the screen for composing an email, have also been taken care of. Furthermore, the calendar add-on Lightning is now a standard part of the program, there is a new wizard for the first use and only MailExtensions add-ons are supported. The changelog for this release looks like this:

What’s New

  • OpenPGP: Added option to disable email subject encryption


  • OpenPGP public key import now supports multi-file selection and bulk accepting imported keys
  • MailExtensions: getComposeDetails will wait for “compose-editor-ready” event


  • New mail icon was not removed from the system tray at shutdown
  • Place replies in the folder of the message being replied to did not work when using “Reply to List”
  • Thunderbird did not honor the “Run search on server” option when searching messages
  • Highlight color for folders with unread messages wasn’t visible in dark theme
  • OpenPGP: Key were missing from Key Manager
  • OpenPGP: Option to import keys from clipboard always disabled
  • The “Link” button on the large attachments info bar failed to open up Filelink section in Options if the user had not yet configured Filelink
  • Address book: Printing members of a mailing list resulted in incorrect output
  • Unable to connect to LDAP servers configured with a self-signed SSL certificate
  • Autoconfig via LDAP did not work as expected
  • Calendar: Pressing Ctrl-Enter in the new event dialog would create duplicate events
  • Various security fixes
Version number 78.5.1
Release status Final
Operating systems Windows 7, Linux, macOS, Windows 8, Windows 10
Website Mozilla Foundation
License type Freeware