URL: https://docs.unity3d.com/ScriptReference/IntegratedSubsystem.Start.html
ataLayer-initialized', user: { user_unity_id: undefined, user_logged_in: 'no' }, environment: { environment_locale: 'en-us', environment_currency: undefined }});Starts an instance of a subsystem.
Once the instance is started, the subsystem representing this instance is active and can be interacted with.