netbox/netbox/templates/virtualization/vminterface.html

{% extends 'generic/object.html' %}

{% block breadcrumbs %}
  {{ block.super }}
  <li class="breadcrumb-item">
    <a href="{% url 'virtualization:virtualmachine_interfaces' pk=object.virtual_machine.pk %}">{{ object.virtual_machine }}</a>
  </li>
{% endblock %}