fix

wp-content/plugins/robin-image-optimizer/assets/js/lazy-load.js

@@ -0,0 +1,11 @@
+/*if ('loading' in HTMLImageElement.prototype && wbcr_robin.wpCompatibleLazy === 'yes') {
+    //loading="lazy" in WP >= 5.5
+} else {
+}*/
+
+const el = document.querySelectorAll('img');
+const observer = lozad(el, {
+    loaded: function (el) {
+    },
+});
+observer.observe();