Given that PolymerFire is not supported for use with Polymer 3 it would make sense to have some use examples for using RXFire with Polymer 3. Most important are Firebase Initialization. User Authentication, including sign in and sign out, and reading and writing data to Firestore and Realtime Database. Perhaps using something like the Polymer 3 Starter Kit.
I’m struggling to find anything. Plenty of info and examples for Angular but nothing for Polymer 3. It’s extremely frustrating given Firebase, Angular, and Polymer are all in the Google camp. Google sort it out and support and resource Polymer 3 properly please.