That is what was once announced, but (a couple years) after that Mozilla announcement, control was indeed transferred to a new group of people who now govern th

That is what was once announced, but (a couple years) after that Mozilla announcement, control was indeed transferred to a new group of people who now govern the project and do indeed work on new features as well. There are more details on the website, e.g.: https://blog.mozilla.org/thunderbird/2014/11/thunderbird-reorganizes-at-2014-toronto-summit/ https://blog.mozilla.org/thunderbird/2014/11/thunderbird-reo...