hehe/user/plugins/form/templates/forms/fields/columns/columns.html.twig

<div class="form-columns {{ field.classes }}">
{% if field.fields %}
    {% set cols = field.fields|length %}
    {% for field in field.fields %}
        {% set value = form.value(field.name) %}
        {% include ["forms/fields/#{field.type}/#{field.type}.html.twig", 'forms/fields/column/column.html.twig'] with {'cols':cols}  %}
    {% endfor %}
{% endif %}
</div>