Is it possible to receive notifications when an email is opened?

Question

Email

Is there any way to make it so that when the recipient opens the letter, a notification about this would be automatically sent without additional actions like "click this button to confirm receipt of the letter"?
I met such a contraption a long time ago in some mailing service. They had the "number of opened letters" parameter in their statistics.

Answer 1

Oh my God. Yes, as many times as possible.
I can do whatever I want with the mail - I can accept, but pretend that I did not accept, I can not accept, but pretend that I received it. I can cut any heading or embed it. Of course, I can’t change the content of the encrypted message, but I can make it so that no links built into it are opened. There are only two
ways to send a notification about the opening of a letter - an indicator in the header (which can be easily cut out) or a beacon with a one-pixel image downloaded from a controlled site (which chokes on disabling downloading links in mail and blocking unproxied tyrnet). Although it should work on free mailers.

Answer 2

It is possible, but there is no reliable way. The mail client can be configured not to send a notification about opening and / or not to download external resources, and mail services such as Google or Yandex upload external links to their servers and you will not track when the recipient opened the letter.

Answer 3

Mailgun seems to let you see the logs, check also sendpulse