<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
  <body>
    <referenceBlock name="head.additional">
      <block class="Chatstack\Chatstack\Block\CodeBlock" name="codeblock" template="codeblock.phtml" />
    </referenceBlock>
  </body>
</page>
