Describe SMTP/envelope情報 here. SMTP mail from (送信アドレス), SMTP rcpt to (受信アドレス) 情報のこと http://im.qmail.jp/im/responsibility.html {{attachment:Screenshot 2024-03-17 at 12-22-28 古い技術について—SMTP現代事情つまみ食い—.png}} Envelope vs Header FROM https://www.xeams.com/difference-envelope-header.htm