Edit File: instance.cls.php
<?php /** * The abstract instance * * @since 3.0 */ namespace LiteSpeed ; defined( 'WPINC' ) || exit ; abstract class Instance { /** * Get the current instance object. To be inherited. * * @since 3.0 * @access public */ public static function get_instance() { if ( ! isset( static::$_instance ) ) { static::$_instance = new static() ; } return static::$_instance ; } }