Can't install Xamarin.Firebase.Common on shared Xamarin project

First of all, you cannot use the Xamarin.Firebase.Common package, which has a dependency on Android, in the shared project of your Xamarin.Forms app.

Secondly, you cannot use native exceptions in the shared, cross-platform context. Therefore, you won’t have access to FirebaseNetworkException, etc. in the shared project.

Instead, since you’re already using the Plugin.FirebaseAuth, you need to catch FirebaseAuthException instead, which wraps the different platform-specific exceptions and hides them behind error codes.

Your code should be looking something like this:

try
{
    var provider = new OAuthProvider("google.com");
    var result = await CrossFirebaseAuth.Current.Instance.SignInWithProviderAsync(provider);
}
catch (FirebaseAuthException e)
{
    switch(e.ErrorType)
    {
        case ErrorType.NetWork:
            //handle network error 
            break;
        case InvalidCredentials:
            //handle invalid credentials
            break;
        //...
        default: break;
    }
}

There’s a full list for the mapping of the ErrorType enum to the Firebase exceptions in the documentation.

Therefore, wherever you need to catch an exception, you can check the ErrorType and perform the appropriate operation or show an error message to the user.