Huh? This has nothing to do with the unsubscribe-header thingy. This is about when you for example provide a URL that contains a token in an email, which you ex

Huh? This has nothing to do with the unsubscribe-header thingy. This is about when you for example provide a URL that contains a token in an email, which you exchange for an authentication token once the user visits the URL. Some people implement that page to automatically do the exchange on page load, instead of waiting for the user to click on a button.