[gls2ro]

I also don't agree with deprecating this without a feasible alternative to ask the user of a page something with a simple line, that works well on desktop and mobile without any extra CSS needed to make it mobile friendly.

The original proposal of the author of that issue is to use NotificationAPI but that is not supported in IE. And a lot of web apps in B2B are extensively using alert and confirm.

I feel this is a solution for websites abusing this feature that will cause a lot of maintenance effort spent in a lot of legit applications.

Here is a better alternative (of course with a lot of drawbacks that I cannot think now in 5 minutes): make the dialog timeout after a period by default. When timing out the dialog disappears without any action/change happening in the rendered page.