Enabling a placeholder in Smart Snippets to include other plugins

The Smart Snippet has an additional placeholder field. In order to render the placeholder, the template code shoudl look like this (item1 and item2 are some TextField variables):

{% load placeholder_tags %}
     <div>
      {{ item1 }}

     <br><br> {% render_placeholder plugins %} <br>

      {{ item2 }}
     </div>

{% endwith %}