Android app nowgetting "requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE be specified" crash

Question

I have a Visual Studio 2022 Xamarin Android app (I know it's now unsupported) that has worked fine for many years. It uses NuGet packages for Firebase, etc. After November 4 (probably the Firebase November 15 release), when the app is in the background and a notification comes in, it crashes with "FATAL EXCEPTION: Firebase-MyFirebaseMessagingService[AndroidRuntime] java.lang.IllegalArgumentException: requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE be specified when creating a PendingIntent.[AndroidRuntime]". I do already use Flag_Immutable in my PendingIntent calls, and like I said, this always worked fine. Upon much investigation, I figure I have to upgrade from Xamarin to .NET8. I am trying that, but I am having issues as to which NuGet packages to use so as not to cause compatibility problems. The packages in question are: Newtonsoft.Json, FirebaseMessaging, Xamarin.Android.Support (probably now AndroidX?), Xamarin.Essentials, Xamarin.AndroidX.LegacySupport, and Xamarin.GooglePlayServices. Main questions are:

1. Is there a way to fix that error just within my current Xamarin project without having to migrate? I have tried many things, including adding AndroidX.Work.Runtime (which I can't because it's incomatible, etc.).
2. If I do have to migrate, is there a list of the best packages to use for .NET8?

Answer 1

If I do have to migrate, is there a list of the best packages to use for .NET8?

Firstly, you can read this MAUI support policy, check the different .NET version's end of support date.

Then you can migrate to the specific .NET version.

I create a .NET for android demo(.NET 9), And I install following nuget packages

Microsoft.Maui.Essentials 9.0.40   Newtonsoft.Json 13.0.3   Xamarin.AndroidX.Legacy.Support.Core.Utils 1.0.0.31 and Xamarin.AndroidX.Work.Runtime 2.10.0.3 Xamarin.Firebase.Messaging 124.1.0.1, No compatibility problems. By the way some of Xamarin.GooglePlayServices have been added in the Xamarin.Firebase.Messaging 124.1.0.1.

You can create a demo like us，then implement the basic function, if it works in your side. Then you can migrate to the .NET for android.

If you have .net for android or migrated issue, you could select .NET tag and then select .NET MAUI child tag.