strict dmarc - SERP Analysis

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https://support.dmarcdigests.com/article/1270-relaxed-vs-strict-alignment

https://dmarcadvisor.com/dmarc-strict-or-relaxed/

https://www.mailhardener.com/kb/dmarc

https://dmarcreport.com/blog/determining-dmarc-authentication-with-relaxed-and-strict-alignment-modes/

https://powerdmarc.com/dmarc-alignment/

https://support.valimail.com/en/articles/8466455-dmarc-strict-vs-relaxed-alignment

https://support.google.com/a/answer/2466580%3Fhl%3Den

https://www.twilio.com/docs/sendgrid/ui/sending-email/dmarc