Not sure whether it is correct to submit that as an issue, since it's partly a question, in which case I apologise for the mistake.
I've noticed that background message handler fails to handle messages when the app is killed in case the battery optimisation for the app is enabled within the system settings (which it is by default). To clarify, I do have a WAKE_LOCK permission setup in my android manifest.
I was wondering if anybody had faced the similar issue, and if there's any way to bypass it, or if it's an expected system behaviour?