On 28 Feb 2018, I posted in this forum ("How to unsubscribe from contest announcement emails?") asking how to manage my account settings so as to no longer receive emails announcing contests. There was a response from "Admin Testing" who then promptly closed the thread to further replies.
"Admin Testing" said to use the unsubscribe link at the bottom of all emails. I'm attaching screenshots of one of the recent contest emails from photo.net (two screenshots, so as to show the full extent of the message with scrolling). I don't see any unsubscribe link. Even dragging the pointer over the whole message, to see if the highlighting colors would reveal a link, did not reveal any unsubscribe link.
I'm using Apple's Mail Version 11.2 (3445.5.20) on macOS Version 10.13.1 (17D47).
This missing or invisible unsubscribe link, along with the fact that I'm getting two copies of every contest announcement email (sent within minutes of each other, to the same recipient address), are indications of fundamental problems at photo.net or its email list contractor.
What can be done about this?