This is a continuation of the thread - [[https://support.mozilla.org/bm/questions/1533447|Thunderbird is being managed by your organisation CAUSE: Bitdefender]] The solution of deleting the Registry Key does not work. It simply comes back after reboot. I have engaged with BitDefender support and they suggested the same thing - they also added to uninstall TB which I am not going to do. The issue is that the BitDefender extension is not installed in a normal way, and cannot be removed. The settings in BitDefender do not make any difference, I cannot change settings in a Thunderbird account eg change a folder location, it looks like it works, but it actually does not. I did find in the about:config '''extensions.webextensions.uuids''' key has the bdThunderbird@bitdefender.com entry but there is no indication as to what other strings belong to the entry and I do not to mess things up. I do realize this is a BitDefender issue, and i did follow up with their support but I am wondering if anyone has solved this annoying issue. Thanks