pma/templates/database/structure/add_prefix.twig

<form id="ajax_form" action="{{ url('/database/structure/add-prefix-table') }}" method="post">
  {{ get_hidden_inputs(url_params) }}

  <fieldset class="pma-fieldset input">
    <table>
      <tr>
        <td>{% trans 'Add prefix' %}</td>
        <td>
          <input type="text" name="add_prefix" id="txtPrefix" aria-label="{% trans 'Add prefix' %}">
        </td>
      </tr>
      <tr>
    </table>
  </fieldset>
</form>