How do you prompt a user before they leave a webpage with a custom message?

Question

I am trying to use window.confirm because you can set a custom message whereas with window.onbeforeunload, you cannot.

Something like window.onbeforeunload = () => window.confirm('Are you sure you want to leave') would be nice, but it doesn't work.

You cannot. It is a security risk. Please see [this awesome explainer](https://stackoverflow.com/questions/1119289/how-to-show-the-are-you-sure-you-want-to-navigate-away-from-this-page-when-ch) — stever, Jan 24 '19 at 19:12
@stever Gonna assume you meant to link the first answer. Thought it'd be more in depth, but thanks anyway. — sdfsdf, Jan 24 '19 at 21:16

score 0 · Answer 1 · answered Jan 24 '19 at 19:16

0

You could try this. I think this is what you asked for

window.onbeforeunload = popup;

function popup() {
  return 'I see you are leaving the site';
}

answered Jan 24 '19 at 19:16

Jesper Wistrom

1

This used to work, but virtually all browsers removed support for custom `unbeforeunload` text around 2017. – apsillers Jan 24 '19 at 19:18

1 Answers1