Sorry I think I know what happened, when I created the new account I used Chrome, but to activate it by default I have Firefox configured, it turns out that in Firefox I had another user account started at that moment and I guess that was the one reason, anyway I have done a test from scratch, I have registered and I am waiting to receive the mail to activate it, now I tell you the result.
Now just arrived, thank you very much, it has taken a little longer to arrive, I was doing tests with other accounts and it has taken a few minutes but it has arrived.
Do you think that when they update the plugin, they will correct this problem or will I have to be deleting this code every time there is an update?
Thank you very much for your response, I have deleted that code as you said and then I have sent the activation email to a hotmail account, but the result remains the same, the mail does not arrive.
I have WP Mail SMTP installed, the email is authenticated.
