Get raw menu from Bolt, no submenus, do something after halfway through loop

Get raw menu from bolt settings

{% set footerthemamenu = app.config.get('menu/samen-verder') %}
<ul>
  {% for item in footerthemamenu %}
    {# Get record of the menu item, to create the real routes #}
    {% setcontent itemrecord = item.path %}
    
    <li>
      <a href="{{ itemrecord.link }}">{{ item.label }}</a>
    </li>

    {% if loop.index == ((footerthemamenu|length)/2)|round(0, 'ceil') %}
    {# close list and open a new one after hald of the loop #}
    </ul>
    <ul>

    {% endif %}
  {% endfor %}
</ul>