sync email when email found

sync_email_on_pageload.php

<?php
add_action("wp_footer", function () {
    if (is_checkout()) {
        echo '<script>jQuery(document).ready(function ($) {
                setTimeout(function () {
                    let emailField = $("#billing_email");
                    if (emailField.length > 0) {
                        emailField.trigger("change");
                    }
                }, 1000);
            });</script>';
    }
});