diff --git a/assets/javascripts/discourse-assign/pre-initializers/extend-category-for-assign.js.es6 b/assets/javascripts/discourse-assign/pre-initializers/extend-category-for-assign.js.es6
index 3bb263e..143022d 100644
--- a/assets/javascripts/discourse-assign/pre-initializers/extend-category-for-assign.js.es6
+++ b/assets/javascripts/discourse-assign/pre-initializers/extend-category-for-assign.js.es6
@@ -11,6 +11,11 @@ export default {
         "custom_fields.enable_unassigned_filter",
         {
           get(fieldName) {
+            // not sure how this is possible but appears to happen in some cases
+            // in test
+            if (!this && !this.custom_fields) {
+              return false;
+            }
             return Ember.get(this.custom_fields, fieldName) === "true";
           }
         }