diff --git a/src/helpers/utilities.ts b/src/helpers/utilities.ts
index 69230b9..d25a790 100644
--- a/src/helpers/utilities.ts
+++ b/src/helpers/utilities.ts
@@ -177,7 +177,7 @@ export class Utilities {
    * Utility to check if the code is running inside of an add-in.
    */
   static get isAddin() {
-    return Utilities.host !== HostType.WEB;
+    return !!Utilities.host && Utilities.host !== HostType.WEB;
   }
 
   /**