diff --git a/lib/core/utils/preload-cssom.js b/lib/core/utils/preload-cssom.js
index 43c2ffcc24..c919d023c4 100644
--- a/lib/core/utils/preload-cssom.js
+++ b/lib/core/utils/preload-cssom.js
@@ -187,9 +187,13 @@ function getStylesheetsFromDocumentFragment(rootNode, convertDataToStylesheet) {
  * @returns {Array<Object>}
  */
 function getStylesheetsFromDocument(rootNode) {
-  return Array.from(rootNode.styleSheets).filter(sheet =>
-    filterMediaIsPrint(sheet.media.mediaText)
-  );
+  return Array.from(rootNode.styleSheets).filter(sheet => {
+    if (!sheet.media) {
+      return false;
+    }
+
+    return filterMediaIsPrint(sheet.media.mediaText);
+  });
 }
 
 /**