SMTP Mail.ru gives an error, how to solve?

Question

Email

The client has mail on mail.ru, you need to configure smtp.
I'm using the Easy WP SMTP plugin.
I enter all ports, the client entered the password from his mailbox, but the test letter is not sent.
I googled and found this documentation for mail.ru
It turns out that you need to create a password for an external application?
And for what? What exactly is that external offer that requires SMTP?

Answer 1

https://help.mail.ru/mail/security/protection/external
Is something unclear here?

Answer 2

Mail RU Without declaring war, it recently breaks properly functioning mail accounts. Including accounts from mail for the domain. that have been working for years. And suddenly the error "Authentication failed" starts SUDDENLY in the mail client working on imap\smtp\pop. We go into the web face of the mailer, set the "Password for external application" in the account settings, after 5 minutes you can use it to re-authorize the mail client and everything starts working. The old password from now on only works for entering the mail through the web face. These are the pies if someone comes across a mail client that suddenly refused to work on a phone or some other device. This is a disservice to improving security. Very doubtful, I must say. There is no warning.
It is extremely remarkable that this process takes place in stages, according to incomprehensible rules, some old accounts continue to work with one password, and by the way, the newly created ones work fine and do not ask for a password for an external application.
No less remarkable is the fact that one such random client once lost his outlook and did not log in to any. Until they created a password for an external application, then outlook worked, but on an iPhone with the same account, the mail client both worked and continued to work with the old password.