Why is opendmarc rejecting mail from firefox.com? It looks like their SPF record matches their sending address and does pass:
v=spf1 mx a include:amazonses.com include:mail.zendesk.com -all
/var/log/maillog:
postfix/smtpd[19221]: connect from a59-48.smtp-out.us-west-2.amazonses.com[54.240.59.48]
postfix/smtpd[19221]: Anonymous TLS connection established from a59-48.smtp-out.us-west-2.amazonses.com[54.240.59.48]: TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)
postfix/smtpd[19221]: 559B1453AE7: client=a59-48.smtp-out.us-west-2.amazonses.com[54.240.59.48]
postfix/cleanup[19242]: 559B1453AE7: message-id=<01010174e1286c9e-b6d5f59b-d47f-4978-8979-ddc31c5b6170-000000@us-west-2.amazonses.com>
opendkim[25641]: 559B1453AE7: a59-48.smtp-out.us-west-2.amazonses.com [54.240.59.48] not internal
opendkim[25641]: 559B1453AE7: not authenticated
opendkim[25641]: 559B1453AE7: message has signatures from firefox.com, amazonses.com
opendkim[25641]: 559B1453AE7: DKIM verification successful
opendmarc[25631]: 559B1453AE7 ignoring Authentication-Results at 1 from ip-172-31-2-211.ec2.internal
opendmarc[25631]: 559B1453AE7: SPF(mailfrom): 01010174e1286c9e-b6d5f59b-d47f-4978-8979-ddc31c5b6170-000000@us-west-2.amazonses.com pass
opendmarc[25631]: 559B1453AE7: **firefox.com fail**
postfix/cleanup[19242]: 559B1453AE7: milter-reject: END-OF-MESSAGE from a59-48.smtp-out.us-west-2.amazonses.com[54.240.59.48]: 5.7.1 rejected by DMARC policy for firefox.com; from=<01010174e1286c9e-b6d5f59b-d47f-4978-8979-ddc31c5b6170-000000@us-west-2.amazonses.com> to=<redacted@redacted.com> proto=ESMTP helo=<a59-48.smtp-out.us-west-2.amazonses.com>