diff --git a/src/main/javascript/view/MainView.js b/src/main/javascript/view/MainView.js
index 529f7377..0a19f4ff 100644
--- a/src/main/javascript/view/MainView.js
+++ b/src/main/javascript/view/MainView.js
@@ -68,7 +68,9 @@ SwaggerUi.Views.MainView = Backbone.View.extend({
       } else {
 
         // Default validator
-        this.model.validatorUrl = window.location.protocol + '//online.swagger.io/validator';
+        if(window.location.protocol.startsWith('http')) {
+          this.model.validatorUrl = window.location.protocol + '//online.swagger.io/validator';
+        }
       }
     }
   },