diff --git a/waitForKeyElements.js b/waitForKeyElements.js
index 97cba3c..f144eda 100644
--- a/waitForKeyElements.js
+++ b/waitForKeyElements.js
@@ -33,8 +33,10 @@ function waitForKeyElements(
 ) {
     let targetNodes, btargetsFound;
 
-    if (typeof iframeSelector == "undefined") targetNodes = selectorTxt;
-    else targetNodes = iframeSelector.contents().find(selectorTxt);
+    if (typeof iframeSelector == "undefined")
+        targetNodes = document.querySelector(selectorTxt);
+    else
+        targetNodes = iframeSelector.contentDocument.querySelector(selectorTxt);
 
     if (targetNodes && targetNodes.length > 0) {
         btargetsFound = true;