Youtube Tv App on Xfinity Flex Device not working for background feature.

Youtube Tv has a feature whereby if you are looking at a live TV show and then hit the back button to go back to the live TV guide, the currently running channel will continue running in the background while you navigate the guide. This feature does not appear to work when using the Youtube TV app on the flex device. However, if I use the Youtube TV app on a firestick device the feature works. Is there any way to get this feature working on the flex device?