mod_http_xep227: Initialize XEP-0227 XML mod_storage_xep0227 only writes if there is XML already for a user (it uses the presence of an existing <user> element as an indicator that an account exists, although technically this is not something Prosody itself does, so it's a little weird).

<tr>
  <th>What is {x} {op} {y}?</th><td>
    <input name="captcha_challenge" type="hidden" value="{challenge}">
    <input name="captcha_reply" pattern="[0-9]+" required type="number">
  </td></tr>