FCM: Is the order in which messages are sent preserved?

Question

If I send to a client message msg1 and then I send another message msg2, can I be absolutely sure that the client will receive first msg1 and only after that msg2 ?

Answer 1

From documentation is clear that FCM does not guarantee message order.

That means that you might receive msg1 before msg2, but there is no guarantee that messages will be received in that order. You might as well receive msg2 before msg1.

You should not code your application logic to expect msg1 will always appear before mgs2.

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