title: woocommerce order prefix won't show up in export
body: <p>The order numbers in our Woocommerce webshop need to have a certain prefix, so I added this code to the functions.php of our theme:</p>
  
  <pre><code>add_filter( 'woocommerce_order_number', 'webendev_woocommerce_order_number', 1, 2 );
  
  
  function webendev_woocommerce_order_number( $oldnumber, $order ) {
      return 'WEB' . $order-&gt;id;
  }
  </code></pre>
  
  <p>It works alright while viewing it on the frontend and backend, but when I try to export it with store export, download an invoice or anything else the prefix is not include. How can I force the prefix onto the order ID in exports, PDF's, etc?</p>