A collection of snippets for a Wordpress theme's function.php file to clean up the output

clean_wordpress_head.php

<?php

/**
* Core output
**/

//Remove the generator tag
remove_action('wp_head', 'wp_generator');

//Remove the frontend admin bar while in development
add_filter('show_admin_bar', '__return_false');

//Remove shortlinks from head
remove_action('wp_head', 'wp_shortlink_wp_head', 10, 0);

//remove manifest link
//http://wpsmackdown.com/wordpress-cleanup-wp-head/
remove_action('wp_head', 'wlwmanifest_link');
remove_action('wp_head', 'rsd_link');
remove_action('wp_head', 'adjacent_posts_rel_link_wp_head', 10, 0);

//Remove emoji frontend files added in 4.2
remove_action('wp_head', 'print_emoji_detection_script', 7);
remove_action('wp_print_styles', 'print_emoji_styles');
//Remove s.w.org prefetch link
add_filter( 'emoji_svg_url', '__return_false' );
//Remove emoji admin files added in 4.2 - THIS CAN BREAK EDITOR FUNCTIONALITY
//remove_action('admin_print_scripts', 'print_emoji_detection_script');
//remove_action('admin_print_styles', 'print_emoji_styles');

//Disable the json api and remove the head link
add_filter('rest_enabled', '__return_false');
add_filter('rest_jsonp_enabled', '__return_false');
remove_action('wp_head', 'rest_output_link_wp_head', 10);

//oEmbed stuff
//Remove the REST API endpoint.
remove_action('rest_api_init', 'wp_oembed_register_route');
//Turn off oEmbed auto discovery.
//Don't filter oEmbed results.
remove_filter('oembed_dataparse', 'wp_filter_oembed_result', 10);
//Remove oEmbed discovery links.
remove_action('wp_head', 'wp_oembed_add_discovery_links');
//Remove oEmbed-specific JavaScript from the front-end and back-end.
remove_action('wp_head', 'wp_oembed_add_host_js');

//Remove the posts menu item if the site doesn't need a blog
//function post_remove () {
//   remove_menu_page('edit.php');
//}
//add_action('admin_menu', 'post_remove');
//Also remove the new post and other links from the adminbar
//function remove_wp_nodes() {
//    global $wp_admin_bar;
//    $wp_admin_bar->remove_node( 'new-post' );
//    $wp_admin_bar->remove_node( 'new-link' );
//    $wp_admin_bar->remove_node( 'new-media' );
//}
//add_action( 'admin_bar_menu', 'remove_wp_nodes', 999 );

/**
* Third party extensions that do annoying things
**/

//Remove All Yoast HTML Comments
//https://gist.github.com/paulcollett/4c81c4f6eb85334ba076
function go_yoast() {
  if (defined('WPSEO_VERSION')){
      add_action('get_header',function (){ ob_start(function ($o){
          return preg_replace('/\n?<.*?yoast.*?>/mi','',$o); }); });
      add_action('wp_head',function (){ ob_end_flush(); }, 999);
  }
}
add_action('plugins_loaded', 'go_yoast');

//Move the yoast seo stuff to the bottom of the admin pages
function yoasttobottom() {
			return 'low';
		}
add_filter( 'wpseo_metabox_prio', 'yoasttobottom');

//Remove WPML generator tag
if (!empty($GLOBALS['sitepress'])) {
    add_action( 'wp_head', function() {
        remove_action(current_filter(), array ($GLOBALS['sitepress'], 'meta_generator_tag')); 
    }, 0 );
}