Strip inline signatures also if signing key is not present?
Schleuder (more specifically 'mail-gpg') does not strip the signature from the content of an inline-signed message body if the signature could not be verified — that case includes a missing key. That behaviour is inconsistent with other behaviour and also not helpful (in our context).
I don't think that we should much more effort in supporting PGP-inline, I'm rather posting it for the record so we don't lose it.