Change is_subscriber and was_subscriber to cached_properties

core/templates/core/user_tools.jinja

@@ -91,7 +91,7 @@
 <h4>{% trans %}Elections{% endtrans %}</h4>
 <ul>
     <li><a href="{{ url('election:list') }}">{% trans %}See available elections{% endtrans %}</a></li>
-    {%- if user.is_subscribed() -%}
+    {%- if user.is_subscribed -%}
     <li><a href="{{ url('election:create') }}">{% trans %}Create a new election{% endtrans %}</a></li>
     {%- endif -%}
 </ul>