[atesti]

I have seen Outlook and other systems click on every link in our mailings. Using a sandboxed browser.

How can one click unsubscribe work here? Mail scanners, virus scanners and even Microsoft's own spam filters would probably click these links!

[zie]

The unsubscribe links are POST, not GET's. That's basically the entire safety net.

[atesti]

Really? I have not seen a <form> html element in an email in decades! Do you mean a list-unsubscribe header? I mean the hyperlink at the end of an email with "unsubscribe". I think it would be good if that unsubscribe link opens a page where one would need to press one more button to prove that it is not automatically involved by url scanners. But this would not be "one click" unsubscribe anymore. So how can this be solved? Why is not everybody constantly auto-unsubscribed who uses office 365 or hotmail?

[zie]

I was talking about https://datatracker.ietf.org/doc/html/rfc8058. Where the URL is in the headers as List-Unsubscribe: <URL>

A 2 page overview is here: https://certified-senders.org/wp-content/uploads/2017/07/CSA...