Thunderbird 78.6.0 has been released today. The new version of the email client is available for all supported operating systems -- Windows, Mac OS, and Linux -- as a direct update from within the client and a standalone download.
Thunderbird 78.6.0 is a security update that includes new features, changes, and a lot of fixes. Users may select Help > About Thunderbird to run a manual check for updates from within the clients (note that the update may not be available right away and that it may take a few hours before Thunderbird will pick it up).
Thunderbird 78.6.0The functionality of MailExtensions, add-ons that Thunderbird supports, has been extended in this release. The function browser.windows.openDefaultBrowser() is now supported and developers may also use the menus API in messages being composed.
Additionally, there are two API changes: first, that the allowScriptsToClose argument is honored in windows.create API functions, and second, that accountld will reflect the account the message belongs to and not what is stored in message headers.
The remaining non-security changes are all bug fixes, and there are quite a lot of them.
Thunderbird 78.6.0 includes two visual improvements next to all that. Mail notification popups will display using a dark theme if dark theme is active, and several areas (folder icon, message list and contact side bar) have received visual improvements.
Thunderbird"s development team lists a single known issue that is affecting Mac OS Big Sur users: According to the release notes, Thunderbird may perform sluggish on devices running this version of Mac OS.
Thunderbird 78.6.0 includes eight security fixes. One of the eight security issues received the highest severity rating of critical, four a rating of high (second highest), one of moderate, and two of low.
Now You: Anything you would like to see in Thunderbird? Have you updated yet?