Edit File: header-embed.php
<?php /** * Contains the post embed header template * * When a post is embedded in an iframe, this file is used to create the header output * if the active theme does not include a header-embed.php template. * * @package WordPress * @subpackage Theme_Compat * @since 4.5.0 */ if ( ! headers_sent() ) { header( 'X-WP-embed: true' ); } ?> <!DOCTYPE html> <html <?php language_attributes(); ?> class="no-js"> <head> <title><?php echo wp_get_document_title(); ?></title> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <?php /** * Prints scripts or data in the embed template head tag. * * @since 4.4.0 */ do_action( 'embed_head' ); ?> </head> <body <?php body_class(); ?>>