Thunderbird has actually come back to Mozilla around 2017: https://blog.thunderbird.net/2017/05/thunderbirds-future-home/ https://blog.thunderbird.net/2017/05/t

Thunderbird has actually come back to Mozilla around 2017: https://blog.thunderbird.net/2017/05/thunderbirds-future-home/ https://blog.thunderbird.net/2017/05/thunderbirds-future-hom... And has been operating as a fully fledged subsidiary of the foundation since 2020: https://blog.thunderbird.net/2020/01/thunderbirds-new-home/ https://blog.thunderbird.net/2020/01/thunderbirds-new-home/