When onNewToken is called in Firebase?

Public Method Summary voidonDeletedMessages() Called when the Firebase Cloud Messaging server deletes pending messages.voidonNewToken(String token) Called when a new token for the default Firebase project is generated.FirebaseMessagingService – Google firebase.google.com › docs › android › com › google › firebase › messaging

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What is Firebase instance ID?

Firebase Instance ID provides a unique identifier for each app instance and a mechanism to authenticate and authorize actions (example: sending FCM messages). Instance ID is stable except when: App deletes Instance ID. App is restored on a new device. User uninstalls/reinstall the app.

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