am 0643d7c4: docs: add new tag for tasks doc

          </a> <span class="new">new!</span></li>

          <li><a href="<?cs var:toroot ?>guide/topics/fundamentals/tasks-and-back-stack.html">

            <span class="en">Tasks and Back Stack</span>

          </a></li>

          </a> <span class="new">new!</span></li>

        </ul>

      </li>

      <li class="toggle-list">