id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux 22348,templates that extend admin/change_form throw difficult-to-track error,django@…,nobody,"The following template runs fine; {% extends ""admin/change_form.html"" %} {% block breadcrumbs %} {% endblock %} {% block content %} Blah {% endblock %} However omitting the breadcrumbs block should be valid - you will just get the breadcrumbs block from the parent; {% extends ""admin/change_form.html"" %} {% block content %} Blah {% endblock %} however this throws a difficult to trace error; NoReverseMatch at /admin/membership/reports/company/membershippaid/ Reverse for 'app_list' with arguments '()' and keyword arguments '{u'app_label': ''}' not found. 1 pattern(s) tried: [u'admin/(?P\\w+)/$'] The admin/change_form.html template contains this; {% url 'admin:app_list' app_label=opts.app_label %} which i think is the code generating the error due to opts being empty. It is possible that my system (upgraded from 1.2.3) is causing opts to be blank - not sure how to test this, however putting [{{ opts }}] into the template shows that opts is empty. ",Uncategorized,closed,Template system,1.6,Normal,needsinfo,template extends admin change_form,,Unreviewed,0,0,0,0,0,0