I recently upgraded my project to Swift3 and upgraded the Firebase module to version 4.0.0. After fixing all the errors and warnings, when I tried to send a push notification from the console. I found that sending notifications using one device works fine. However, sending to a specific user segment is not performed; which I need most for my application. When sending a user segment, I just check the identifier of the iOS package and try to send all the devices on which the application is installed.
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