About FCM

FCM is a long link between Google server and GMS application for push notification maintained by Google in Android.

The general workflow is that the application server sends the message to Google server, Google server pushes the message to GMS application, GMS application passes it to the application through broadcast, and the application decides whether to send notification and notification content based on the received FCM message.

When GMS notifies the application through FCM broadcast, if the application is not running, it will appear Failed to broadcast to stopped app. FCMfix is mainly to solve this problem.