Refactor for better re-usability

Introduce common base template for plan views
Move breadcrumbs to own file for easy referencing
Load common fullcalendar base files in base template
Introduce new block for other fullcalendar operations

AKPlan/templates/AKPlan/plan_base.html

+{% extends "base.html" %}
+
+{% load fontawesome_5 %}
+{% load i18n %}
+{% load static %}
+
+{% block imports %}
+    {% get_current_language as LANGUAGE_CODE %}
+
+    <link href='{% static 'AKPlan/fullcalendar/core/main.css' %}' rel='stylesheet' />
+
+    <script src='{% static 'AKPlan/fullcalendar/core/main.js' %}'></script>
+    {% with 'AKPlan/fullcalendar/core/locales/'|add:LANGUAGE_CODE|add:'.js' as locale_file %}
+    <script src="{% static locale_file %}"></script>
+    {% endwith %}
+    <script src='{% static 'AKPlan/fullcalendar/bootstrap/main.js' %}'></script>
+
+    {% block fullcalendar %}{% endblock %}
+{% endblock imports %}
+
+{% block footer_custom %}
+    {% if event.contact_email %}
+        <h4>
+            <a href="mailto:{{ event.contact_email }}">{% fa5_icon "envelope" "far" %} {% trans "Write to organizers of this event for questions and comments" %}</a>
+        </h4>
+    {% endif %}
+{% endblock %}

AKPlan/templates/AKPlan/plan_breadcrumbs.html

+{% load i18n %}
+{% load tags_AKModel %}
+
+<li class="breadcrumb-item">
+    {% if 'AKDashboard'|check_app_installed %}
+        <a href="{% url 'dashboard:dashboard' %}">AKPlanning</a>
+    {% else %}
+        AKPlanning
+    {% endif %}
+</li>
+<li class="breadcrumb-item">{{ event.slug }}</li>
+<li class="breadcrumb-item">
+    <a href="{% url 'plan:plan_overview' event_slug=event.slug %}">{% trans "AK Plan" %}</a>
+</li>

AKPlan/templates/AKPlan/plan_index.html

-{% extends "base.html" %}
+{% extends "AKPlan/plan_base.html" %}
 
 {% load fontawesome_5 %}
 {% load i18n %}
-{% load tags_AKModel %}
 {% load static %}
 {% load tz %}
 
 
-{% block imports %}
+{% block fullcalendar %}
     {% get_current_language as LANGUAGE_CODE %}
 
-    <link href='{% static 'AKPlan/fullcalendar/core/main.css' %}' rel='stylesheet' />
     <link href='{% static 'AKPlan/fullcalendar/timeline/main.css' %}' rel='stylesheet' />
     <link href='{% static 'AKPlan/fullcalendar/resource-timeline/main.css' %}' rel='stylesheet' />
     <link href='{% static 'AKPlan/fullcalendar/resource-timeline/main.min.css' %}' rel='stylesheet' />
 
-    <script src='{% static 'AKPlan/fullcalendar/core/main.js' %}'></script>
-    {% with 'AKPlan/fullcalendar/core/locales/'|add:LANGUAGE_CODE|add:'.js' as locale_file %}
-    <script src="{% static locale_file %}"></script>
-    {% endwith %}
     <script src='{% static 'AKPlan/fullcalendar/timeline/main.js' %}'></script>
     <script src='{% static 'AKPlan/fullcalendar/resource-common/main.js' %}'></script>
     <script src='{% static 'AKPlan/fullcalendar/resource-timeline/main.js' %}'></script>
-    <script src='{% static 'AKPlan/fullcalendar/bootstrap/main.js' %}'></script>
 
     <script>
         document.addEventListener('DOMContentLoaded', function() {
@@ -90,20 +83,11 @@
             plan.render();
         });
     </script>
-{% endblock imports %}
+{% endblock %}
 
 
 {% block breadcrumbs %}
-    <li class="breadcrumb-item">
-    {% if 'AKDashboard'|check_app_installed %}
-        <a href="{% url 'dashboard:dashboard' %}">AKPlanning</a>
-    {% else %}
-        AKPlanning
-    {% endif %}
-</li>
-<li class="breadcrumb-item">{{ event.slug }}</li>
-    <li class="breadcrumb-item"><a
-        href="{% url 'plan:plan_overview' event_slug=event.slug %}">{% trans "AK Plan" %}</a></li>
+    {% include "AKPlan/plan_breadcrumbs.html" %}
 {% endblock %}
 
 
@@ -136,12 +120,3 @@
         </div>
     {% endtimezone %}
 {% endblock %}
-
-
-{% block footer_custom %}
-    {% if event.contact_email %}
-        <h4>
-            <a href="mailto:{{ event.contact_email }}">{% fa5_icon "envelope" "far" %} {% trans "Write to organizers of this event for questions and comments" %}</a>
-        </h4>
-    {% endif %}
-{% endblock %}