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action is not described

after_signup_user action-hook . WP 4.4.0

Fires after a user's signup information has been written to the database.

Usage

add_action( 'after_signup_user', 'action_function_name_5416', 10, 4 );
function action_function_name_5416( $user, $user_email, $key, $meta ){
	// action...
}
$user(string)
The user's requested login name.
$user_email(string)
The user's email address.
$key(string)
The user's activation key.
$meta(array)
Signup meta data.
Default: empty array

Where the hook is called

wpmu_signup_user()
wp-includes/ms-functions.php 812
do_action( 'after_signup_user', $user, $user_email, $key, $meta );

Where the hook is used (in WP core)

wp-includes/ms-default-filters.php 29
add_action( 'after_signup_user', 'wpmu_signup_user_notification', 10, 4 );