Configure Thunderbird 128 e2e encryption with GnuPG
It took me longer than I would have liked to setup the latest Thunderbird 128 (Supernova!) to use my existing GnuPG-based encryption setup, for a large part because TB defaults to its own more straight-forward built-in defaults for key management, and so I’m going to publish the recipe here to save you some time, hopefully.
All the details, at various levels of obviousness, can be found on this Mozilla wiki page, but here I’m going to make the whole sequence more obvious.