diff --git a/app/controllers/my_modules_controller.rb b/app/controllers/my_modules_controller.rb
index d0cfb854c..7764d6c4e 100644
--- a/app/controllers/my_modules_controller.rb
+++ b/app/controllers/my_modules_controller.rb
@@ -99,7 +99,7 @@ class MyModulesController < ApplicationController
         }
       end
       format.json do
-        render json: @my_module, serializer: Lists::MyModuleSerializer, user: current_user
+        render json: @my_module, serializer: Lists::MyModuleSerializer, controller: self, user: current_user
       end
     end
   end
diff --git a/app/serializers/lists/my_module_serializer.rb b/app/serializers/lists/my_module_serializer.rb
index 36425ab67..b48ba5648 100644
--- a/app/serializers/lists/my_module_serializer.rb
+++ b/app/serializers/lists/my_module_serializer.rb
@@ -145,7 +145,9 @@ module Lists
 
     def tags_html
       # legacy canvas support
-      ApplicationController.new.render_to_string(
+      return '' unless @instance_options[:controller]
+
+      @instance_options[:controller].render_to_string(
         partial: 'canvas/tags',
         locals: { my_module: object },
         formats: :html