Thunderbird 91.4.1 email client released with security fixes
A new version of the open source email client Thunderbird is now available. Thunderbird 91.4.1 is a security update for the email client that also includes a good dozen non-security enhancements and fixes.
The official release date was December 17, 2021, but the new version was not offered on a fully patched system on December 19, 2021.
You can check the installed version by selecting Help > About Thunderbird from the menu. If the menu is not displayed, tap the Alt key to display it. Thunderbird runs a manual check for updates and will install new versions, if available.
The official download site lists Thunderbird 91.4.0 as the latest version, and the only source for the new version is the classic FTP site at the time of writing.
The security fixes have not yet been published on the official site. Security notices for the Thunderbird website. You may want to check there later to find out if the information has been posted.
Release notes are available and can be accessed here. The new version fixes various attachments, account setup, and saving issues in the email client.
- Thunderbird would display save dialogs for certain types of attachments, such as ICS attachments, instead of opening them.
- Attachments for IMAP accounts could not be saved if the usernames contained special characters.
- Sometimes the temporary files that Thunderbird creates to forward attachments contained the wrong extension.
- Outlook showed S/MIME signatures as invalid.
- On Mac OS, URL input boxes in content tabs displayed a search glass icon by mistake.
- The message bars did not use high-contrast theme colors.
- Thunderbird could crash if messages with autocrypt headers were loaded.
- The account manager cut off the server hostnames.
- Passwords with non-ASCII characters were not supported during account setup.
- Account settings would sometimes not retain values.
- Folder selection of virtual folders was not retained when a folder contained non-ASCII characters.
- Message headers were not included for saved EML or HTML messages.
- The private web page field was not included when a contact was exported to a vCard.
- Disabling all plugins in Troubleshoot mode would not disable plugins after a reboot.
- The FileLink provider icon was not always displayed for FileLink attachments.
- The upload would still show as an icon when the FileLink upload failed.
- Long event names for multi-day events do not wrap.
- Various UX improvements and unspecified themes.