Today, I randomly came across a forum mail in the Proton Mail web application, which had the following warning banner at the top:
As I found out while reading the linked article, this message relates to both message content and sender verification. All forum mails I have received so far have no verification implemented (the domain does not have SPF configured, the mail header does not refer to mail.hypr.land for DKIM and the (lenient) DMARC entry is inherited from hypr.land):
Interestingly, the automated mails from [email protected] I received July last year did have verification implemented (this should still be the case, since hypr.land has SPF configured).
I don’t really know what to do with this information, but since every other mail I have received so far seems to have everything configured in this regard (even some random spam mail), I wanted to share this discovery just in case you are unaware of it, or in case I am unaware of the reason not to implement DKIM and SPF.