diff --git a/lib/service_worker/background/windows.js b/lib/service_worker/background/windows.js
index d696b991..e36a2248 100644
--- a/lib/service_worker/background/windows.js
+++ b/lib/service_worker/background/windows.js
@@ -177,7 +177,7 @@ async function hideWindows(windowId) {
 				var _didIteratorError = false;
 				var _iteratorError = undefined;
 				try {
-					for (var _iterator = displaylayouts[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+					for (let _iterator = displaylayouts[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
 						var displaylayout = _step.value;
 						globalDisplayInfo.push(displaylayout.bounds);
 					}