Preload custom user fields when viewing flag queue

app/serializers/flagged_user_serializer.rb

@@ -3,7 +3,8 @@ class FlaggedUserSerializer < BasicUserSerializer
              :can_be_deleted,
              :post_count,
              :topic_count,
-             :ip_address
+             :ip_address,
+             :custom_fields
 
   def can_delete_all_posts
     scope.can_delete_all_posts?(object)
@@ -17,4 +18,19 @@ class FlaggedUserSerializer < BasicUserSerializer
     object.ip_address.try(:to_s)
   end
 
+  def custom_fields
+    fields = User.whitelisted_user_custom_fields(scope)
+
+    if scope.can_edit?(object)
+      fields += DiscoursePluginRegistry.serialized_current_user_fields.to_a
+    end
+
+    result = {}
+    fields.each do |k|
+      result[k] = object.custom_fields[k] if object.custom_fields[k].present?
+    end
+
+    result
+  end
+
 end