iPadOS 18 SwiftUI TabView: Default to sidebar hidden for .sidebarAdaptable?

I have a SwiftUO view containing a TabView with .tabViewStyle(.sidebarAdaptable). It works nicely, save that the sidebar defaults to visible/open. Can I set the default to closed/hidden until the user clicks the sidebar icon in the tabbar?

Forgot to mention: I'm using .defaultAdaptableTabBarPlacement(.tabBar) and it still does this. Is it due to my using tab groups in my view?

iPadOS 18 SwiftUI TabView: Default to sidebar hidden for .sidebarAdaptable?
 
 
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