I face a very strange problem; I had a previous version of my application published using GCM 8.4.0 which worked fine. I updated some code, without changing anything about GCM and I realised that the messages where not received anymore when the application was in background. This on several different devices.
As I was unable to find any explanation, I migrated to FCM. I made few unsuccessful attempts and it began to work !?! Then I was able to send several different messages successfully without changing anything! Houra!!!!
Just before generating my signed APK, I made a last test! Arrggghhhhh.... messages were not received anymore when the application was in background!!!!
I made the test with my server, with Advance REST Request, in the same conditions as I used for successful attempts and no way, it works when the application is in foreground but no more at all when the application is in background!!!
Did you exeperience such problem???
I precise that when I receive a message with the application in foreground and I generate a notification from it, There are 2 different behaviors:
When the application is able to receive it in background, the notification remains when I swipe the app out from the recent apps list.
When the application is not able to receive it in background, as in my current case, the generated notification is removed when I swipe the application out.
Does it mean something useful?
Edit
I updated to 9.2.0 but the problem remains.