'On the Mozilla Thunderbird blog it was announced that for the future Thunderbird 78 release, planned for summer 2020, they will add built-in functionality for email encryption and digital signatures using the OpenPGP standard. This addresses a feature request opened on Bugzilla almost 20 years ago and has been one of the top voted bugs for most of that period.'

-- source: https://it.slashdot.org/story/19/10/08/209254

Cheers, Peter