mod_http_oauth2: Make note about handling repeated RFC 6749 states > If an authorization code is used more than once, the authorization > server MUST deny the request and SHOULD revoke (when possible) all > tokens previously issued based on that authorization code. We should follow the SHOULD. The MUST is already covered by removing the code state from the cache.

<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>