New user notification doesn’t include activation link

When adding new users through the Dashboard, I’ve noticed that the notification email sent to a user when then have been added to WordPress doesn’t work correctly. Included in the email is the following line, however you’ll notice that the registration key is missing and the link is not rendered properly.

To set your password, visit the following address: http://www.domain.com/wp-login.php

I did some digging around, outputting the contents of wp_mail like so:

    add_filter('wp_mail', function($email) {
        var_dump($email);
        return $email;
    }, 1);

And seeing this for the new user notification email:

array(5) {
  ["to"]=>
  string(20) "test+19@domain.com"
  ["subject"]=>
  string(47) "[My Great Blog] Your username and password info"
  ["message"]=>
  string(224) "Username: test19

To set your password, visit the following address:

<http://www.domain.com/wp-login.php?action=rp&key=1nTPsJVMk3H2eEM3Wgpm&login=test19>

http://www.domain.com/wp-login.php
"
  ["headers"]=>
  string(0) ""
  ["attachments"]=>
  array(0) {
  }
}

What’s weird is that it sort of includes a correct link, but the HTML is malformed (no A href=””), and it’s missing the closing . I have confirmed this on WordPress Trac.

Anyone have any insight onto why this is not working, seems like such a crucial part of a website.

Version 4.9.8.

Already set ‘wp_mail_content_type’ to text/html’.

WordPress 4.9.0 introduced 2 filters into the new user notification mail function (wp_new_user_notification):

• wp_new_user_notification_email – to customise the email sent to User
• wp_new_user_notification_email_admin – to customise the email email sent to Admin

We can ignore the second as this is the email sent to the admin the format is different from that in your question. wp_new_user_notification_email on the other hand allows you to modify the ‘to’, ‘subject’, ‘message’ and ‘headers’ before these are sent to the wp_mail() function.

However, you intercepted the wp_mail filter which fires immediately after wp_new_user_notification_email and everything looks fine at that point, so the issue must be later. The only remaining place that the message could be filtered is through the wp_mail filter.

If you are convinced that there is no issue with charset or client side email, then look for any other calls to add_filter(‘wp_mail’, …). Also check out the source code of the email received.

Sorry I can’t be more help. This is an interesting question and I look forward to hearing finally what the solution is or any other suggestions.