NavigationSplitView TabView Toolbar Clash

I would like to create a master-detail view inside the Settings screen for my Mac app. I am trying to use a NavigationSplitView nested inside the top-level Settings TabView. (Reduced code below).

However, the sidebar of the NavigationSplitView interferes with the TabView - the TabView appears to be in the detail of the NavigationSplitView even though it is its parent. I have seen others having the reverse issues with TabViews in NavigationSplitViews. Is this a known bug please?

struct SettingsView: View {
    var body: some View {
        TabView {
            GeneralSettingsView()
                .tabItem {
                    Label("General", systemImage: "gear") }
                .tag(SettingsSection.general)
            
            TypesView()
                .tabItem {
                    Label("Types", systemImage: "star") }
                .tag(SettingsSection.types)
        }
        .frame(width: 375, height: 150)
    }
}

struct TypesView: View {
    
    @Environment(\.modelContext) private var modelContext
    @Query private var types: [ItemType]
    
    @State private var selectedType: ItemType?
    
    var body: some View {
        NavigationSplitView {
            List {
                    ForEach(types) { type in
                        NavigationLink {
                            TypeView(type: type)
                        } label: {
                            Text(type.name)
                        }
                    }
            }
        } detail: {
            Text("Select a Type")
        }
    }
}