Display all hooks/actions fired during the current page load [WordPress]

display_all_hooks.php

class MyTracker {

  static $hooks;

  static function track_hooks( ) {
    $filter = current_filter();
    if ( ! empty($GLOBALS['wp_filter'][$filter]) ) {
      foreach ( $GLOBALS['wp_filter'][$filter] as $priority => $tag_hooks ) {
        foreach ( $tag_hooks as $hook ) {
          if ( is_array($hook['function']) )  {
            if ( is_object($hook['function'][0]) ) {
              $func = get_class($hook['function'][0]) . '->' . $hook['function'][1];
            } elseif ( is_string($hook['function'][0]) ) {
              $func = $hook['function'][0] . '::' . $hook['function'][1];
            }
          } elseif( $hook['function'] instanceof Closure ) {
            $func = 'a closure';
          } elseif( is_string($hook['function']) ) {
            $func = $hook['function'];
          }
          self::$hooks[] = 'On hook <b>"' . $filter . '"</b> run <b>'. $func . '</b> at priority ' . $priority;
        }
      }
    }
  }

}

add_action( 'all', array('MyTracker', 'track_hooks') );

add_action( 'shutdown', function() {
    echo implode( '<br />', MyTracker::$hooks );
}, 9999);