Register the template tag. Also use the view name, not the tab name, when...

Register the template tag. Also use the view name, not the tab name, when fetching the tab to render.

django/website/tabbed_page/templatetags/render_tab.py

+from django import template
 from django.template.loader import render_to_string
 
 from ..tab_pool import get_tab
 
 
+register = template.Library()
+
+
+@register.filter(name='render_tab')
 def render_tab(tab_instance):
-    tab = get_tab(tab_instance.name)
+    tab = get_tab(tab_instance.view_name)
 
     template_name = tab.template_name