Safari has them https://developer.apple.com/notifications/safari-push-notifications/

Firefox Has them https://developer.mozilla.org/en-US/docs/Web/API/notification

Chrome Has them https://developers.google.com/web/updates/2015/03/push-notifications-on-the-open-web?hl=en

No one cares about Internet Explorer.. at least support the other three.

Supporting Safari notifications would cover all Mac users as well.

When a new email comes, a notification should appear... when the notification is clicked it should open up the browser to that email.

settings should include:

Client: notifications on or off

Admin: allow notifications