Thunderbird 78.6.0 is out: here is what is new

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 78.6.0
The 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.
- OpenPGP: lots of fixes on this front, including fixes for importing keys on Mac OS (that failed), verification of clear signed UTF-8 text, for using decrypt and open/save as functionality with encrypted attachments, and discovery of online keys via the key manager on Linux. Engineers fixed another OpenPGP issue that showed the wrong key after importing a secret key in the properties, and improved inline PGP parsing.
- Address Book: Fixed that the address book view did not update after chaning the name format, and that some columns did not display data (even when data was available).
- Calendar: Fixed that two "home" calendars were displayed on new profiles, that ICS files could not be imporated in CalDAV calendards, and improved the Dark Theme on Linux.
- MailExtensions: Fixed that HTTP refresh in browser content did not work, and that messageDisplayScripts failed to run in the main window.
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?


You said that Outlook isn’t your main email client, so which is your main one?
I think its thunderbird
It is Mozilla Thunderbird.
Awesome! This actually solved my problem… what a stupid bug.
If this is the same bug that I’ve encountered, there may be another fix: (1) hover over open Outlook item in Taskbar, cursor up to hover over Outlook window item, and right-click; (2) this should give you Restore / Move / Size / Minimize / Maximize — choose Move or Size; (3) use your cursor keys, going arbitrarily N/S/E/W, to try to move or size the Outlook window back into view. Basically, the app behaves as though it were open in a 0x0 window, or at a location that’s offscreen, and this will frequently work to resize and/or move the window. Don’t forget to close while resized/moved, so that Outlook remembers the size/position for next time.
THANK YOU Claude!!! I could get the main window to launch but could not get any other message window to show on the desktop. You are my hero!!!!
Solved my issue! 6 years later and this is still problem…
Fantastic. Thank you. Size did the trick.
This solved my Outlook problem, too. Thank you. :)
Thank you so much, this started happening to me today and was causing big problems. You are a life saver, I hope I can help you in some way some day.
You are a god – thank you!
thanks a lot…. work like charm.. :-)
Yah…thanks Claude. I’ve been having the same problem and tried all the suggestions…your solution was the answer. It had resized itself to a 0/0 box. Cheers
Excellent post. This had me baffled even trying to accurately describe the problem. This fixed it for me.
Thank you
Thanks a lot for the article. Don’t know why it happenend, don’t know how it got fixed, but it was really annoying and now it works :-)
Thanks a lot. I was facing this issue from past 3 week. I tried everything but no resolution. The issue was happening intermittently and mainly when I was changing the display of screen ( as i use 2 monitors). The only option i had was to do system restore. But thanks to you.
I’ve been tried to sole this problem for 12hours. Your comment about changing the display of screen helped me a lot!! Thanks!!
Thank you…don’t know why this happened but your instructions helped me fix it. Running Windows 10 and office pro 2007
Great tip! Thanks!
Worked for me, too – thank you!!!
It’s Worked for me, too
thank you very much!
I had a similar issue with Outlook 2013 on Windows 10 and this helped me to fix it. Thank you very much!
Thank you so much. Solved!
Considering you published this in 2012, incredible not been debugged by Microsoft.
Thank you again. M
This problem was faced by only one user logging to TS 2008 r2 using outlook 2010.The issue was resolved.
Thanks.
Great tip. Thank you!!!! If it helps, I had to use the Control Key and the arrow keys at the same time to bring my window back into view. Worked like a charm.
Thank you, this worked !!!!
Man, you are a fucking god. Thanks a lot, what an annoying bug!!
Awesome, this post solved the issue. Many thanks!