WooCommerce 3: disable JSON/LD format

functions.php

<?php // Do not include this if already open! Code goes in theme functions.php.
/*
 * Remove the default WooCommerce 3 JSON/LD structured data format
 */
function remove_output_structured_data() {
  remove_action( 'wp_footer', array( WC()->structured_data, 'output_structured_data' ), 10 ); // Frontend pages
  remove_action( 'woocommerce_email_order_details', array( WC()->structured_data, 'output_email_structured_data' ), 30 ); // Emails
}

add_action( 'init', 'remove_output_structured_data' );