Use different Site Icon (FavIcon) for different page/post

// Use different Site Icon (FavIcon) for different page/post
add_filter( 'get_site_icon_url','change_site_favicon', 10, 3 );
function change_site_favicon ($url, $size, $blog_id) {
  global $post;
  // Use is_single() to show in single post
  if ( is_page( 13 ) ) $url = 'http://wpufdemo.local/wp-content/uploads/2021/07/Design-dream-img-37cdb084.png';
  return $url;
  }