title: React native navigation stack navigator header not fixed at top for web
body: <p>This very basic app with a single stack navigator doesn't behave as expected for web. On iOS/Android the header stays in place and the screen scrolls under the header. For web the header doesn't stay fixed on top. See this snack <a href="https://snack.expo.io/@tositsa/nested-stacks-fixed-header-issue-2" rel="nofollow noreferrer">https://snack.expo.io/@tositsa/nested-stacks-fixed-header-issue-2</a></p>
  <p>I think this might be a bug in react-native-navigation or react-native-web, but I'd love to see if there is a workaround somehow.</p>