In wp-includes/user.php, the docs for the new_user_email_content hook specify that both arguments are of type string. The second argument, new_user_email is actually an array, containing the new address as well as a hash. It is declared on line 3726 in the same file.
https://core.trac.wordpress.org/browser/tags/6.6/src/wp-includes/user.php#L3774
You're right, I completely misread the docblock. Sorry about this. I'll close the ticket. Thank you.
Hi there!
The new_user_email_content shows second args array. See https://github.com/WordPress/wordpress-develop/blob/trunk/src/wp-includes/user.php#L3761-L3782
Buy me a coffee
Spenden / Donate/**
* Filters the text of the email sent when a change of user email address is attempted.
*
* The following strings have a special meaning and will get replaced dynamically:
* - ###USERNAME### The current user's username.
* - ###ADMIN_URL### The link to click on to confirm the email change.
* - ###EMAIL### The new email.
* - ###SITENAME### The name of the site.
* - ###SITEURL### The URL to the site.
*
* @since MU (3.0.0)
* @since 4.9.0 This filter is no longer Multisite specific.
*
* @param string $email_text Text in the email.
* @param array $new_user_email {
* Data relating to the new user email address.
*
* @type string $hash The secure hash used in the confirmation link URL.
* @type string $newemail The proposed new email address.
* }
*/
$content = apply_filters( 'new_user_email_content', $email_text, $new_user_email );