Accept sent on behalf of as the sender address
* src/mail.cpp (Mail::updateOOMData_o): Cache sent on behalf. (Mail::updateSigstate): Fallback to sent on behalf. (m_sent_on_behalf): New cache variable. * src/oomhelp.cpp (get_sender_SentRepresentingAddress): New.
Outlook clearly shows in the mail:
"firstname.lastname@example.org at behalf of email@example.com"
So we can accept "firstname.lastname@example.org" also as the sender address
as it is visible.
- GnuPG-Bug-ID: T4110