Capture default user profile fields at Membership Checkout using Register Helper

my_default_wp_user_checkout_fields.php

<?php
/**
 * Add Website and Biographical Info to Membership Checkout
 */
function my_default_wp_user_checkout_fields() {
	if ( class_exists( 'PMProRH_Field') ) {
		pmprorh_add_checkout_box( 'additional', 'Additional Information' );
		$fields = array();
	
		//user_url field
		$fields[] = new PMProRH_Field(
			'url', 
			'text', 
			array(
				'label'=>'Website',
				'size'=>40,
				'profile'=>true,
				'required'=>false,
			)
		);

		//user_description field
		$fields[] = new PMProRH_Field(
			'description', 
			'textarea', 
			array(
				'label'=>'Biographical Info',
				'size'=>40,
				'profile'=>true,
				'required'=>false,
			)
		);

		foreach( $fields as $field ) {
			pmprorh_add_registration_field( 'additional', $field );	
		}
	}
}
add_action( 'init', 'my_default_wp_user_checkout_fields' );