Mail security software at large companies opens every link in a message before the person it was sent to ever sees it. If the unsubscribe link in a newsletter footer takes effect the moment it is opened, that reader is off the list at delivery, and nobody gets an error to look at.
The reader never asked to leave. They wait for an email that stopped coming, and on the sending side the list just gets smaller with a clean log behind it. The same gateway opens the confirmation link in a double opt-in message, which means a subscription can be confirmed before the human it was sent to has opened the mail.
Popwire is one trending story per post, ranked by view count, with the outlets that reported it named on the post. It sends one email each morning at 07:50 carrying the day's eight highest-ranked stories, batched out through Resend a hundred addresses at a time, each message personalised with that reader's own unsubscribe link.
Both links ask before they act
The confirmation link and the unsubscribe link answer an opened link with a page that has one button on it and nothing else. Nothing is written down until that button is pressed and the browser sends the answer back. The page tells the reader why, in the words they see: "We ask because automated mail scanners follow links in email, and we would rather not unsubscribe you by accident."
Every digest also carries the two headers a mail client reads to put its own Unsubscribe control at the top of the message. That control does not open anything. It sends its answer directly, which is what the one-click standard for it was written to do, and Popwire answers it with a bare acknowledgement and no page at all. So the reader who wants out in one press gets one press, and the machine reading their mail gets a button it has no way to press.
| In the message | What opening it does | What actually writes |
|---|---|---|
| Confirmation link | renders a page with one button | the button being pressed |
| Unsubscribe link in the footer | renders a page with one button | the button being pressed |
| The mail client's own Unsubscribe control | nothing is opened | the client's own answer, acknowledged with no page |
| A link wrapped or cut short in transit | a page reading "That link didn't work" | nothing |
The link a mail client broke on the way
Long addresses get wrapped across lines by mail clients, and the code in each link is a fixed shape. Popwire checks that shape before the database is asked anything, so a mangled link comes back as a page saying the link didn't work, with an offer to remove the address by hand. Handed straight to the database, the same mangled value returns a type error and the reader gets a server error page for a link they did nothing wrong with.
Both pages are also marked not to be indexed, on the page itself and in the response, because the address carries a code belonging to one subscriber.
Here is the wire: https://popwire.kynth.studio/kd
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