Enable PGP sign only as default


How can I set enable PGP sign only as a default in compose a message in K9 mail.
I can find this option in the menu (3 dots) when I open a compose new message. But I have to select this every time I compose a message.
I use K9 and open keychain on an Android phone.
Best regards,

You can’t. See Makes PGP sign-only mails very difficult · Issue #2375 · k9mail/k-9 · GitHub