WordPress Cleanup

functions.php

<?php
// ALL OF THIS IS FROM: https://www.linkedin.com/pulse/wp-speed-up-from-ground-alex-knopp
// Post Revisions

// WordPress will simply store every single post revision you create. If your a developer like me then my clients websites change a lot and these post revisions build up. Add the following to your wp-config.php file to stipulate the number of post revisions saved at any one time.

//Define the number of post revisions to be saved
define( 'WP_POST_REVISIONS', 3 );

// WordPress Bloat

// If your coding your own themes and plugins then your probably already aware that WordPress adds its own code here and there and begins to bloat out areas in the dom that arent required. For example, menu classes and ID's and body classes.

// > Clean up the navigation classes and id's

// Remove the ID from the menu item
function clear_nav_menu_item_id($id, $item, $args) {
    return "";
}
add_filter('nav_menu_item_id', 'clear_nav_menu_item_id', 10, 3);


// Remove the class from the menu item
function clear_nav_menu_item_class($classes, $item, $args) {
    return array();
}
add_filter('nav_menu_css_class', 'clear_nav_menu_item_class', 10, 3);

// > Dequeue jQuery Migrate

function dequeue_jquery_migrate( &$scripts){
	if(!is_admin()){
		$scripts->remove( 'jquery');
		$scripts->add( 'jquery', false, array( 'jquery-core' ), '1.10.2' );
	}
}
add_filter( 'wp_default_scripts', 'dequeue_jquery_migrate' );

// > Pesky header code bloat such as RSS links, version generator, post links etc

function removeHeadLinks() {
  remove_action( 'wp_head', 'feed_links_extra', 3 ); // Display the links to the extra feeds such as category feeds
  remove_action( 'wp_head', 'feed_links', 2 ); // Display the links to the general feeds: Post and Comment Feed
  remove_action( 'wp_head', 'rsd_link' ); // Display the link to the Really Simple Discovery service endpoint, EditURI link
  remove_action( 'wp_head', 'wlwmanifest_link' ); // Display the link to the Windows Live Writer manifest file.
  remove_action( 'wp_head', 'index_rel_link' ); // index link
  remove_action( 'wp_head', 'parent_post_rel_link', 10, 0 ); // prev link
  remove_action( 'wp_head', 'start_post_rel_link', 10, 0 ); // start link
  remove_action( 'wp_head', 'adjacent_posts_rel_link', 10, 0 ); // Display relational links for the posts adjacent to the current post.
  remove_action( 'wp_head', 'wp_generator' ); // Display the XHTML generator that is generated on the wp_head hook, WP version
}
add_action('init', 'removeHeadLinks');

// > Disable XMLRPC. More of a security feature than a performance one.

add_filter('xmlrpc_enabled', '__return_false');

// > If your not linkely to be using comments then you wont be using emjois.

function disable_wp_emojicons() {
  // all actions related to emojis
  remove_action( 'admin_print_styles', 'print_emoji_styles' );
  remove_action( 'wp_head', 'print_emoji_detection_script', 7 );
  remove_action( 'admin_print_scripts', 'print_emoji_detection_script' );
  remove_action( 'wp_print_styles', 'print_emoji_styles' );
  remove_filter( 'wp_mail', 'wp_staticize_emoji_for_email' );
  remove_filter( 'the_content_feed', 'wp_staticize_emoji' );
  remove_filter( 'comment_text_rss', 'wp_staticize_emoji' );
  // filter to remove TinyMCE emojis
  add_filter( 'tiny_mce_plugins', 'disable_emojicons_tinymce' );
}
add_action( 'init', 'disable_wp_emojicons' );

function disable_emojicons_tinymce( $plugins ) {
  if ( is_array( $plugins ) ) {
    return array_diff( $plugins, array( 'wpemoji' ) );
  } else {
    return array();
  }
}
add_filter( 'emoji_svg_url', '__return_false' );

// HTML Minify

// You can minify front end code like HTML, CSS and JS with the plugins Ive mentioned above however, you can also do this as part of your own theme development using the following I found on github. Sorry to the author I just cant find you again.

class WP_HTML_Compression {
    protected $compress_css = true;
    protected $compress_js = true;
    protected $info_comment = true;
    protected $remove_comments = true;
 
    protected $html;
    public function __construct($html) {
      if (!empty($html)) {
        $this->parseHTML($html);
      }
    }
    public function __toString() {
      return $this->html;
    }
    protected function bottomComment($raw, $compressed) {
      $raw = strlen($raw);
      $compressed = strlen($compressed);    
      $savings = ($raw-$compressed) / $raw * 100;   
      $savings = round($savings, 2);    
      return '<!-- HTML Minify | Gross page reduction of '.$savings.'% | From '.$raw.' Bytes, To '.$compressed.' Bytes -->';
    }
    protected function minifyHTML($html) {
      $pattern = '/<(?<script>script).*?<\/script\s*>|<(?<style>style).*?<\/style\s*>|<!(?<comment>--).*?-->|<(?<tag>[\/\w.:-]*)(?:".*?"|\'.*?\'|[^\'">]+)*>|(?<text>((<[^!\/\w.:-])?[^<]*)+)|/si';
      preg_match_all($pattern, $html, $matches, PREG_SET_ORDER);
      $overriding = false;
      $raw_tag = false;
      $html = '';
      foreach ($matches as $token) {
        $tag = (isset($token['tag'])) ? strtolower($token['tag']) : null;
        $content = $token[0];
        if (is_null($tag)) {
          if ( !empty($token['script']) ) {
            $strip = $this->compress_js;
          }
          else if ( !empty($token['style']) ) {
            $strip = $this->compress_css;
          }
          else if ($content == '<!--wp-html-compression no compression-->') {
            $overriding = !$overriding;
            continue;
          }
          else if ($this->remove_comments) {
            if (!$overriding && $raw_tag != 'textarea') {
              $content = preg_replace('/<!--(?!\s*(?:\[if [^\]]+]|<!|>))(?:(?!-->).)*-->/s', '', $content);
            }
          }
        }
        else {
          if ($tag == 'pre' || $tag == 'textarea') {
            $raw_tag = $tag;
          }
          else if ($tag == '/pre' || $tag == '/textarea') {
            $raw_tag = false;
          }
          else {
            if ($raw_tag || $overriding) {
              $strip = false;
            }
            else {
              $strip = true;
              $content = preg_replace('/(\s+)(\w++(?<!\baction|\balt|\bcontent|\bsrc)="")/', '$1', $content);
              $content = str_replace(' />', '/>', $content);
            }
          }
        }
        if ($strip) {
          $content = $this->removeWhiteSpace($content);
        }
        $html .= $content;
      }
      return $html;
    }
    public function parseHTML($html) {
      $this->html = $this->minifyHTML($html);
      if ($this->info_comment) {
        $this->html .= "\n" . $this->bottomComment($html, $this->html);
      }
    }
    protected function removeWhiteSpace($str) {
      $str = str_replace("\t", ' ', $str);
      $str = str_replace("\n",  '', $str);
      $str = str_replace("\r",  '', $str);
      while (stristr($str, '  ')) {
        $str = str_replace('  ', ' ', $str);
      }
      return $str;
    }
}
function wp_html_compression_finish($html) {
    return new WP_HTML_Compression($html);
}
function wp_html_compression_start() {
    ob_start('wp_html_compression_finish');
}
add_action('get_header', 'wp_html_compression_start');

// Clean up the Admin Menu

// Whilst this doesn't really help the front end or user experience, it will help you keep your admin view more organised. There are plugins available fo this however, I prefer this route as it can be more flexible when it comes to views not recognised or included in the plugins available.

// This will help you retain all your permissions but remove the menu items from the admin. Helpfull if your client needs admin rights but, you want to keep them away from things they either dont need or are likely to break.

function remove_menus(){
  
  remove_menu_page( 'index.php' ); //Dashboard                  
  remove_menu_page( 'edit-comments.php' );
  remove_menu_page( 'themes.php' );
  remove_menu_page( 'plugins.php' );
  remove_menu_page( 'tools.php' );
  remove_menu_page( 'options-general.php' );
  remove_menu_page( 'edit.php?post_type=acf' ); //ACF Custom Fields
}
add_action( 'admin_menu', 'remove_menus' );