Merge pull request floating-ui#1157 from jacwright/iframe-errors

Fix errors when iframes are destroyed

src/dom-utils/getWindow.js

@@ -5,7 +5,7 @@
 export default function getWindow(node) {
   if (node.toString() !== '[object Window]') {
     const ownerDocument = node.ownerDocument;
-    return ownerDocument ? ownerDocument.defaultView : window;
+    return ownerDocument ? ownerDocument.defaultView || window : window;
   }
 
   return node;