netbox-community-netbox/netbox/templates/inc/panel_table.html

{% load render_table from django_tables2 %}

<div class="card {% if panel_class %}border-{{ panel_class }}{% endif %}">
  {% if heading %}
    <h5 class="card-header{% if panel_class %} text-{{ panel_class }}{% endif %}">{{ heading }}</h5>
  {% endif %}
  <div class="card-body table-responsive">
    {% if table.rows %}
      {% render_table table 'inc/table.html' %}
    {% else %}
      <div class="text-muted">None</div>
    {% endif %}
  </div>
</div>