mod_http_oauth2: Don't return redirects or HTML from token endpoint These are used by the client, not the user, so makes more sense to return JSON directly instead of a redirect or HTML error page when .

<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>