Woocommerce auto update cart on quantity change

functions.php

add_action( 'wp_footer', 'cart_update_qty_script' ); 
function cart_update_qty_script() { 
    if (is_cart()) : 
    ?> 
    <script> 
    jQuery('div.woocommerce').on('change', '.qty', function(){ 
        jQuery("[name='update_cart']").trigger("click");
         }); 
    </script> 
    <?php 
    endif; 
}