How to make sure that letters from the site are saved in Yandex mail?

Question

Mail for domain

There is a site and on its domain there is a mail tied to Yandex.
Also, all kinds of notifications are sent to users from the site from php via Yandex SMTP.
How to make sure that these letters are saved in Yandex in outbox or in some folder?

Answer 1

Send a blind copy (BCC) to a mailbox in Yandex.

Answer 2

Yes, while I was waiting for an answer, I also thought that it was possible to do this.