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We would like to inform you about an important update regarding Firebase Cloud Messaging (FCM). FCM is a service widely used by developers to send push notifications to Android devices supported by Google Play. Previously, developers communicated with FCM using the Legacy HTTP protocol. However, FCM v1 is now available, offering enhanced features and capabilities.
It's crucial to note that Google will cease supporting the FCM legacy HTTP protocol on June 20, 2024. Therefore, all customers are required to migrate their applications and notification payloads to the new format (FCM v1) before this date to ensure seamless functionality.
Additionally, please be informed that the Firebase Cloud Messaging (FCM) legacy API will be deprecated by July 2024.
Refer this retirement announcement post - https://learn.microsoft.com/en-sg/answers/questions/1530615/retirement-announcement-azure-notification-hubs-fc