Feature request: More extensive site permissions, like Notifications

It's great to be able to allow/disallow permissions like camera and mic. Could we take it further and allow something like Notifications? (I'm not sure what Adguard webview is based on, but assuming it's Chromium or Gecko, it should be able to receive "desktop notifications" from sites in the form of push notifs.)

While it would be a good start to just add the notification permission as a setting option, it would also be good to determine whether it would be necessary (or even possible) to either change the browser timeout so that a webpage stays active in the background for longer, change something regarding serviceworkers, or maybe add a persistent Android background service — in other words, do something that lets websites send notifications even when the app is not focused.

Example use case: I use Native Alpha for Facebook, because the FB app is spyware and is known to do "negative testing" to deliberately make users phones run slower. It sure would be nice to get FB notifications as push notifications from Native Alpha!
(P.S. I'm aware of the "Notifications for Facebook" app, but it has significant limitations, and a native—no pun intended—solution would be much better and cross-applicable.)