set "attributes" to true when observing mutations

lib/lazy/content-lazy-loader.js

@@ -58,7 +58,7 @@ this.lazyLoader = this.lazyLoader || (() => {
 					timeoutId = deferLazyLoadEnd(timeoutId, maxTimeoutId, idleTimeoutId, observer, resolve);
 				}
 			});
-			observer.observe(document, { attributeFilter: MONITORED_ATTRIBUTES, subtree: true, childList: true });
+			observer.observe(document, { attributeFilter: MONITORED_ATTRIBUTES, subtree: true, childList: true, attributes: true });
 			injectScript(SCRIPT_BEFORE_PATH);
 		});
 	}