message: Used key from state for each scene
diff: @@ -67,6 +67,7 @@ class NavigationStack extends React.Component<NavigationStackProps, NavigationSt
  return {enterAnim, exitAnim, sharedElements, oldSharedElements};
  }
  render() {
  + var {keys} = this.state;
  var {stateNavigator, title, renderScene} = this.props;
  var {url, oldUrl, crumbs, nextCrumb} = stateNavigator.stateContext;
  return (
  @@ -79,7 +80,7 @@ class NavigationStack extends React.Component<NavigationStackProps, NavigationSt
  onDidNavigateBack={this.onDidNavigateBack}>
  {nextCrumb && crumbs.concat(nextCrumb).map((_, crumb) => (
  <Scene
  - key={crumb}
  + key={keys[crumb]}
  crumb={crumb}
  title={title}
  renderScene={renderScene} />
  