diff --git a/plugin.rb b/plugin.rb
index 3de7396..e7b9df4 100644
--- a/plugin.rb
+++ b/plugin.rb
@@ -498,7 +498,6 @@ SQL
   require_dependency 'topic_list_item_serializer'
   require_dependency 'search_topic_list_item_serializer'
   require_dependency 'suggested_topic_serializer'
-  require_dependency 'category_detailed_serializer'
   require_dependency 'user_summary_serializer'
 
   class ::TopicListItemSerializer
@@ -513,10 +512,6 @@ SQL
     include TopicAnswerMixin
   end
 
-  class ::CategoryDetailedSerializer
-    include TopicAnswerMixin
-  end
-
   class ::UserSummarySerializer::TopicSerializer
     include TopicAnswerMixin
   end