_core = $_core; $this->init(); } /** * Do Init * * @since 9 * @access private */ private function init() { add_action( 'admin_head', array( $this, 'admin_style' ) ); } /** * Add Classic Editor Style to Header if currently edited page is a custom 404 error page * * @since 9 * @access public */ public function admin_style() { // we just ignore whether Gutenberg is used or not, because this classes do not exist if Gutenberg is active if ( get_current_screen()->id == 'page' && $this->_core->get_id() > 0 ) { global $post; $all404pages = $this->_core->get_all_page_ids(); if ( in_array( $post->ID, $all404pages ) ) { ?>