Handle potential error by logging it to the console

Author: josbeir

webroot/js/inject-iframe.js

@@ -96,7 +96,11 @@ if (elem) {
         type: this.getResponseHeader('Content-Type'),
       };
 
-      iframe.contentWindow.postMessage(`ajax-completed$$${JSON.stringify(params)}`, window.location.origin);
+      if (iframe && iframe.contentWindow) {
+        iframe.contentWindow.postMessage(`ajax-completed$$${JSON.stringify(params)}`, window.location.origin);
+      } else {
+        console.warn('DebugKit: Unable to send ajax completion message - iframe not available');
+      }
     }
     if (original) {
       return original.apply(this, [].slice.call(arguments));