var testLabManager = TestLabManager.Instantiate();

IDisposable disposable = null;
disposable = Observable.EveryUpdate().Where(_ => testLabManager.IsTestingScenario).Where(_ => testLabManager.ScenarioNumber >= 0).Subscribe(_ => {
  #if UNITY_EDITOR
  _createButton();
  #else
  _startTest(testLabManager.ScenarioNumber);
  #endif
  disposable.Dispose();
});