Brainstorm: More opportunities for automatic traces

[jhuleatt]

Right now, using the initPerformance flag in FirebaseAppProvider activates Performance Monitoring automatic traces. In addition, SuspenseWithPerf creates a custom trace. Are there other places in Reactfire where it would be useful to include Performance Monitoring traces? For example:

• useFirestoreCollection could log a custom trace with a custom attribute logging the number of documents returned
• any of the use* hooks could log a custom trace

[jhuleatt]

The Profiler API is going stable in React 16.9. That might be a good opportunity to add some react-specific custom traces: facebook/react#15172. The problem is that it requires a special build of React to enable the profiler in production.

[jhuleatt]

Good blog post on profiler API: https://kentcdodds.com/blog/profile-a-react-app-for-performance