//* OPTION 1 – Deferring parsing of JavaScript via functions.php
//* Alternatively, it is possible to carry out the task by editing one of WordPress core files. To defer parsing of JS, this code should be copied to the bottom of your theme’s functions.php file:
function defer_parsing_of_js ( $url ) {
if ( FALSE === strpos( $url, '.js' ) ) return $url;
if ( strpos( $url, 'jquery.js' ) ) return $url;
return "$url' defer ";
}
add_filter( 'clean_url', 'defer_parsing_of_js', 11, 1 );