JQuery rendering

This is normal registering of wordpress and not specific to enfold.
I don’t know how WP-Rocket tries to do so.
if i would like to do so i will first deregister it and than register it back again f.e.

i have sometimes this on my functions.php –
that loads the jquery via cdn from google servers – if it exists (or a internet connection is present)
if not it will load the normal jquery from folder – but i do not have success on loading it in the footer.

if( !is_admin()){ 
    $url = 'https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js'; 
    $test_url = @fopen($url,'r'); 
    if($test_url !== false) { 
        function load_external_jQuery() {
            wp_deregister_script('jquery'); 
            wp_register_script('jquery', 'https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js'); 
            wp_enqueue_script('jquery'); 
        }
        add_action('wp_enqueue_scripts', 'load_external_jQuery'); 
    } else {
        function load_local_jQuery() {
            wp_deregister_script('jquery'); 
            wp_register_script('jquery', '/wp-includes/js/jquery/jquery.js', __FILE__, false, '1.12.4', true); 
            wp_enqueue_script('jquery'); 
        }
    add_action('wp_enqueue_scripts', 'load_local_jQuery'); 
    }
}

i tested it with google loading – and it is no performance profit on it.

but on enfold the avia-compat.js is loaded in the header – maybe this is the reason for inconsitencies if jquery is in the footer (after avia-compat.js)