netbox/netbox/templates/extras/journalentry.html

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

{% block breadcrumbs %}
  {{ block.super }}
  <li class="breadcrumb-item"><a href="{% action_url object.assigned_object 'journal' pk=object.assigned_object.pk %}">{{ object.assigned_object }}</a></li>
{% endblock %}