After a lot of pain I got Firebase cloud messaging to work for my JavaScript PWA and push notifications are sent and received properly. However I did create quite a few Cloud Functions to manage topic registration (from the server then). Now I would like to minimize my use of Cloud Functions, and do as much as possible from the client.
I see at here that the Android client SDK allows managing registration to topics, but I cannot find any such documentation for the JavaScript SDK - is it possible?