Flutter Firebase Messaging

Build or repair production Firebase Messaging integrations without importing stale native or Web assumptions into FlutterFire.

Workflow

1. Inspect before editing:
   • Read pubspec.yaml, pubspec.lock, Flutter/Dart constraints, and the installed firebase_messaging changelog.
   • Identify every supported platform and inspect its existing Firebase/native configuration.
   • Search every messaging listener, token call, background handler, permission request, topic operation, payload parser, presentation path, and notification route.
   • Identify the trusted sender, payload schema, backend registration model, permission UX, and reliability assumptions.
2. Read the relevant sections of references/production-guide.md. Use rg -n '^#|^##' references/production-guide.md to locate sections; do not load the entire reference when a focused section is sufficient.
3. Revalidate version-sensitive facts against current official FlutterFire, Firebase, Android, Apple, or Flutter documentation before relying on them. Prefer installed package source and current official documentation over the reference when they conflict.
4. Fix the shared root cause with the smallest complete change. Reuse the application's existing lifecycle, routing, persistence, authentication, and networking patterns.
5. Validate the affected lifecycle on every supported platform, including release mode where background execution or tree shaking matters.

Reference Routing