diff --git a/lib/browser/guest-window-manager.js b/lib/browser/guest-window-manager.js
index 132b5503f3..88871dc58b 100644
--- a/lib/browser/guest-window-manager.js
+++ b/lib/browser/guest-window-manager.js
@@ -141,13 +141,13 @@ const getGuestWindow = function (guestId) {
 ipcMain.on('ELECTRON_GUEST_WINDOW_MANAGER_WINDOW_OPEN', function (event, url, frameName, disposition, options, additionalFeatures) {
   options = mergeBrowserWindowOptions(event.sender, options)
   event.sender.emit('new-window', event, url, frameName, disposition, options, additionalFeatures)
-  var newGuest = event.newGuest
+  const newGuest = event.newGuest
   if ((event.sender.isGuest() && !event.sender.allowPopups) || event.defaultPrevented) {
-	if (newGuest != undefined && newGuest != null) {
+    if (newGuest != undefined && newGuest != null) {
       event.returnValue = setupGuest(event.sender, frameName, newGuest)
-	} else {
+    } else {
       event.returnValue = null
-	}
+    }
   } else {
     event.returnValue = createGuest(event.sender, url, frameName, options)
   }