You cannot send emails with "any domain you want". There are things like DMARC out there, which check the From:-header, and then use that domain and check SPF and DKIM.
What fruux does is totally correct, they use their own domain as a sender address (envelope-from and From:-header).
You cannot send emails with "any domain you want". There are things like DMARC out there, which check the From:-header, and then use that domain and check SPF and DKIM.
What fruux does is totally correct, they use their own domain as a sender address (envelope-from and From:-header).