diff --git a/docs/api/web-contents.md b/docs/api/web-contents.md
index 35a693d92829..e28d593ab79d 100644
--- a/docs/api/web-contents.md
+++ b/docs/api/web-contents.md
@@ -310,7 +310,7 @@ and allow the page to be unloaded.
 const { BrowserWindow, dialog } = require('electron')
 const win = new BrowserWindow({ width: 800, height: 600 })
 win.webContents.on('will-prevent-unload', (event) => {
-  const choice = dialog.showMessageBox(win, {
+  const choice = dialog.showMessageBoxSync(win, {
     type: 'question',
     buttons: ['Leave', 'Stay'],
     title: 'Do you want to leave this site?',