If "Encrypt by default" is set to "Based on history", MailMate
defaults to OpenGPG all the time, because my entire Sent folder is
encrypted.
However, it is encrypted with two of my own keys, not the
recipients keys, since most of them do not use PGP. I did not
really send an encrypted mail to the other party, I just encrypted
my own Sent folder. That also means I do not want MailMate to
base its prediction based on it. I only want to use
MailMate to encrypt messages when I actually have a key from the
other person.
If I set "Encrypt by default" to "Never", MailMate defaults to
S/MIME, which is what I want for most recipients (because that
leads to S/MIME signing only).
So, I would like to stop MailMate from deciding against S/MIME and
for OpenGPG when I have not actually ever sent encrypted mail to
the recipient.
Two ideas on how to achieve that:
1) MailMate could check for whether it actually has the
public key for the recipient before deciding to enable
OpenGPG. If I do not have the public key, I am fairly unlikely to
have previously sent encrypted mail to the recipient.
2) MailMate could be told to ignore specific keys, because they
are mine and should not count when considering whether I send an
encrypted message. Maybe another setting in Security.plist or
something similar to retiredAddressPattern. Or even being very
clever: checking for private keys available with
GPG (well, at least for key stubs) and ignoring my own keys in the
"based on history" decision.
