"@Reporter: Could you please provide a sample URL/file which helps us to triage the issue further.

Thanks!"

Chrome Apps can't open beforeunload dialogs, see  issue 179684  and  issue 130465 .

The best thing we could do is to fire an event listener in the embedder when the guest has a befoerunload event, and then the embedder could confirm/cancel the dialog. It won't work if the user closes the window though, only when navigating.

For now, as a workaround you can use the webRequest API to cancel the navigations in the embedder. The usage is:

document.querySelector('webview').request.onBeforeRequest.addListener(function(e) { return { cancel: true }; }, {urls: ['<all_urls>']}, ['blocking']);

This will cancel all navigations, but you can have code inside the function to inspect the URL and only cancel in some scenarios. See the documentation in https://developer.chrome.com/extensions/webRequest.

For lfg@chromium.org

"The best thing we could do is to fire an event listener in the embedder when the guest has a befoerunload event, and then the embedder could confirm/cancel the dialog."

It's will be perfect. But at this moment webview does not support that event (https://developer.chrome.com/apps/tags/webview).

"It won't work if the user closes the window though, only when navigating."

This is not so bad.

And thank you for workaround. I'll try to use it

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Can navigation team look into this?

+ekaramad@ and lfg@ who may have some ideas.

I've already added my ideas on c#4. I think this is certainly doable, it just needs an owner.