Browser notification on new review

I think it would be handy for our customers, if they could be informed in the browser (and by mail as an alternative) when a new review is collected in one of their reviewnetworks. Notification by browser would be best because this is mostly used when you go into internet. I don't know which would be easier to develop. An extension or just use the notification feature of the browser. I think we only need the confirmation that our domain can send notification to our customers' browser: Congratulations, you collect a new review with X Stars 👍