Thunderbird Release Notes

Version 60.5.2, first offered to channel users on February 25, 2019

Check out "What’s New" and "Known Issues" for this version of Thunderbird below. As always, you’re encouraged to tell us what you think, or file a bug in Bugzilla. If interested, please see the complete list of changes in this release.

If you have installed Lightning, Thunderbird's Calendar add-on, it will automatically be updated to match the new version of Thunderbird. Refer to this Calendar troubleshooting article in case of problems.

System Requirements: • Window: Windows 7, Windows Server 2008 R2 or later • Mac: Mac OS X 10.9 or later • Linux: GTK+ 3.4 or higher. Details here.

Please refer to Release Notes for version 60.0 to see the list of improvements and fixed issues.

What’s New

  • fixed

    Crash when using "Send to > Mail recipient" on Windows under some circumstances (MAPI interface)

  • fixed

    UTF-8 support for MAPISendMail

  • fixed

    Problem with S/MIME certificate verification when receiving email from Outlook (issue introduced in version 60.5.1)

Known Issues

  • unresolved

    Changes to the MAPI interface have caused problems when sending a file from the Windows desktop or a folder via "Sent to > Mail recipient" or via an external application like an office package, for example LibreOffice. To solve this problem, reinstall Thunderbird 60.5.2 from one of these locations: (unsupported 64bit version).
    Files with non-ASCII characters in their name also cause a malfunction. Two alternative workarounds exist:

    • On Windows 10, set the system code page to UTF-8 (beta feature, see Region Settings, system locale)
    • Reset this registry entry
      HKLM\SOFTWARE\Clients\Mail\Mozilla Thunderbird - SupportUTF8 to 0

  • unresolved

    Due to changes in the Mozilla platform profiles stored on Windows network shares addressed via drive letters are now addressed via UNC

  • unresolved

    Chat: Twitter not working due to API changes at