The Parking Lot release is always the top most release in a Story Map and cannot be collapsed. I'd like to be able to both collapse it like I can on other releases so that I can see the top steps bar and the epics in a specific release.
Thank you for your idea. This was done intentionally since the parking lot starts off as your playground as you are adding features. In that case it is important to keep it visible. We do not currently have plans to make changes here but we will continue to monitor customer feedback on this idea.