we have server-side support for ADM (Amazon's Kindle Device push) as well as support for Microsofts' deprecated MPNS (Microsoft Push Notification Service) and SimplePush (from Firefox).

I was wondering if we should remove those, on the master branch, going forward ? 

Would mean that UPS would be just supporting:
* APNs (HTTP/2 only)
* FCM (via HTTP only)
* WNS (Windows Push Notification Services)

How do folks feel about that ? Anyone actively using ADM, SimplePush or MPNS?