diff --git a/lib/renderer/window-setup.js b/lib/renderer/window-setup.js
index f7328c9b0c..530907856e 100644
--- a/lib/renderer/window-setup.js
+++ b/lib/renderer/window-setup.js
@@ -32,7 +32,7 @@ function BrowserWindowProxy (ipcRenderer, guestId) {
   this.closed = false
 
   ipcRenderer.once(`ELECTRON_GUEST_WINDOW_MANAGER_WINDOW_CLOSED_${guestId}`, () => {
-    removeProxy(this.guestId)
+    removeProxy(guestId)
     this.closed = true
   })