mod_ignore_host_chatstates: Discard chat state messages sent to a bare host Prevents annoying error replies to be sent in reply to such empty chat state messages. Useful in combination with modules that handle messages to a host.

<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>