I didn't realize that modern email clients as #thunderbird obfuscated the subject of a message, just showing "..." instead of the real one. I knew #deltachat did that since the beginning, maybe it's something related to #autocrypt
Anyway, that's great news since this is something that you won't have to remember again when writing #gpg encrypted messages.
@aluaces
It's part of #autocrypt effort previously known as "memory hole" specification (https://github.com/autocrypt/memoryhole) with a standard draft at https://datatracker.ietf.org/doc/draft-autocrypt-lamps-protected-headers/
More recent repository is at https://github.com/autocrypt/protected-headers