Cleanup initial WordPress installation

In functions.php add:

	// remove emoji support
 	remove_action('wp_head', 'print_emoji_detection_script', 7);
 	remove_action('wp_print_styles', 'print_emoji_styles');

	// Remove rss feed links
	remove_action( 'wp_head', 'feed_links_extra', 3 );
	remove_action( 'wp_head', 'feed_links', 2 );

	// remove wp-embed
	add_action( 'wp_footer', function(){
		wp_dequeue_script( 'wp-embed' );
	});


	add_action( 'wp_enqueue_scripts', function(){
		// remove block library css
		wp_dequeue_style( 'wp-block-library' );
		// remove comment reply JS
		wp_dequeue_script( 'comment-reply' );
	} );

Also for deffer .js files:

function defer_parsing_of_js($url){
 	if (is_admin()){ return $url;} //don't break WP Admin
 	if (false === strpos($url, '.js')){ return $url;}
 	if (strpos($url, 'jquery.js')){ return $url;}
 	return str_replace(' src', ' defer src', $url);
}
add_filter('script_loader_tag', 'defer_parsing_of_js', 10);