Error with Custom Login URL

Hi,

We have a custom login URL setup with the Hide Backend feature. We also have a popular code snippet that redirects user on the frontend login page when using the Elementor login form as follows:

add_action( 'wp_login_failed', 'elementor_form_login_fail', 9999999 );
function elementor_form_login_fail( $username ) {
    $referrer = $_SERVER['HTTP_REFERER'];  // where did the post submission come from?
    // if there's a valid referrer, and it's not the default log-in screen
    if ((!empty($referrer) && !strstr($referrer,'wp-login') && !strstr($referrer,'wp-admin') )) {
        //redirect back to the referrer page, appending the login=failed parameter and removing any previous query strings
        //maybe could be smarter here and parse/rebuild the query strings from the referrer if they are important
        wp_redirect(preg_replace('/\?.*/', '', $referrer) . '?login=failed' );
        exit;
    }
}
// This is also important. Make sure that the redirect still runs if the username and/or password are empty.
add_action( 'wp_authenticate', 'elementor_form_login_empty', 1, 2 );
function elementor_form_login_empty( $username, $pwd ) {
    $referrer = $_SERVER['HTTP_REFERER'];  // where did the post submission come from?
 if ( empty( $username ) || empty( $pwd ) ) {
    if ((!strstr($referrer,'wp-login') && !strstr($referrer,'wp-admin') )) {
        //redirect back to the referrer page, appending the login=failed parameter and removing any previous query strings
        //maybe could be smarter here and parse/rebuild the query strings from the referrer if they are important
        wp_redirect(preg_replace('/\?.*/', '', $referrer) . '?login=failed' );
        exit;
    }
   exit();
 }
}

We have found is this code snippet does not work with iThemes hide backend feature. The backend URL loads with ‘?login=failed’ appended to the URL and we are unable to login to wp-admin.