diff --git a/README.md b/README.md
index 89b3ce6..165d2f5 100644
--- a/README.md
+++ b/README.md
@@ -146,6 +146,7 @@ Use these attributes on your HTML element like this:
 | data-initinview | boolean: true | Set this to true if you want the resource to execute (for example video to play) when the element is in view.
 
 ## Changelog
+* v2.0 use IntersectionObserver instead of scroll listener, for better performance.
 * v1.1.901 betterify example page
 * v1.1.9 remove gulp and rollup and use webpack instead
     * use Babel 7
diff --git a/src/lazyframe.js b/src/lazyframe.js
index d8418da..f79495a 100644
--- a/src/lazyframe.js
+++ b/src/lazyframe.js
@@ -100,7 +100,7 @@ const Lazyframe = () => {
 
   function loop(el) {
 
-    if (el instanceof HTMLElement === false ||
+    if (!(el instanceof HTMLElement) ||
       el.classList.contains('lazyframe--loaded')) return;
 
     const lazyframe = {