WordPress at a glance
filter is not described

illegal_user_logins filter-hook . WC 3.7.0

WordPress 4.4 - filters the list of blacklisted usernames.

Usage

add_filter( 'illegal_user_logins', 'filter_function_name_659' );
function filter_function_name_659( $usernames ){
	// filter...

	return $usernames;
}
$usernames(array)
Array of blacklisted usernames.

Changelog

Since 3.7.0 Introduced.

Where the hook is called

wc_create_new_customer_username()
illegal_user_logins
wp_insert_user()
illegal_user_logins
register_new_user()
illegal_user_logins
WP_REST_Users_Controller::check_username()
illegal_user_logins
wpmu_validate_user_signup()
illegal_user_logins
edit_user()
illegal_user_logins
woocommerce/includes/wc-user-functions.php 170
$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );
wp-includes/user.php 1577
$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );
wp-includes/user.php 2447
$illegal_user_logins = array_map( 'strtolower', (array) apply_filters( 'illegal_user_logins', array() ) );
wp-includes/rest-api/endpoints/class-wp-rest-users-controller.php 1137
$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );
wp-includes/ms-functions.php 474
$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );
wp-admin/includes/user.php 193
$illegal_logins = (array) apply_filters( 'illegal_user_logins', array() );

Where the hook is used (in WC core)

Usage not found!