netbox-community-netbox/netbox/templates/dcim/inc/endpoint_connection.html

{% if path.destination_id %}
    {% with endpoint=path.destination %}
        <td>{{ endpoint.parent_object|linkify }}</td>
        <td>{{ endpoint|linkify }}</td>
    {% endwith %}
{% else %}
    <td colspan="2" class="text-muted">Not connected</td>
{% endif %}