Hi, @JoachimKoch.
Are you referring to using web push notifications?
I believe @kpatel’s original post referred to uploading files like a service-worker and manifest.json to a site’s root folder, as mentioned in this article.
I don’t have concrete examples of this implemented on HubSpot, but there seems to be quite a bit of literature on the topic on external blogs.
Please let me know if I’ve misunderstood your goal.