<div>
  <metal:block use-macro="macro:form">
    <metal:block fill-slot="above-buttons">
      <input type="hidden" name="document"
             tal:attributes="value request/document|nothing" />
      <input type="hidden" name="layer"
             tal:attributes="value request/layer|nothing" />
      <input type="hidden" name="node"
             tal:attributes="value request/node|nothing" />
    </metal:block>
  </metal:block>
</div>
