Have you had experience testing push notifications in your projects?

Yes, my experience testing push notifications included verifying the delivery of notifications on various devices and platforms, the correctness of message display and content, as well as testing the application's response to receiving a notification (for example, opening the appropriate screen). I used push service emulation tools as well as real devices for this. It is important to test both foreground and background states of the application, as well as handling different types of notifications (with data, media, etc.).