Problem with multiple drag and drop

I have been trying to get the drag and drop to work on iOS 26 betas. Single drag is okay, but I thought this year we were getting multi-select drag added.

creating a simple object that can be dragged. Using the .draggable and added dropDestination which does trigger. The problem is the dragContainer does nothing. Not really clear what it is supposed to do.

How am I supposed to allow for multiple item drag and drop like the Photos app? In there you can start a drag and tap additional photos to add to the drag. I can do this with a UICollectionView, but not with SwiftUI.

struct DragObject: Codable, Identifiable, Transferable {
    var index: Int
    
    enum Keys: String, CodingKey {
        case index
    }
    
    var id:Int {
        index
    }
    
    public func encode(to encoder: any Encoder) throws {
        var container = encoder.container(keyedBy: Keys.self)
        try container.encode(self.index, forKey: .index)
    }

    static public var transferRepresentation: some TransferRepresentation {
        CodableRepresentation(contentType: .json)
    }
}

@available(iOS 26.0, *)
struct DragDropTestView: View {
    @State var items : [DragObject] = (0..<100).map({ DragObject(index: $0) })
    @State var selected : [DragObject.ID] = []
    
    var body: some View {
        let _ = Self._printChanges()
        ScrollView {
            Text("Selected \(selected)")
            LazyVGrid(columns: [GridItem(.adaptive(minimum: 150, maximum: 180))],
                      alignment: .center,
                      spacing: 10)
            {
                ForEach(items, id: \.index) { item in
                    VStack {
                        Text("\(item.index)")
                    }
                    .frame(width: 100, height: 100)
                    .padding()
                    .background(Color.blue)
                    .cornerRadius(8)
                    .contentShape(.dragPreview, Circle())
                    .draggable(item)
                    .dropDestination(for: DragObject.self) { draggedItems, session in
                        print("Dragged Item Count: \(draggedItems.count)")
                    }
                }
            }
        }
        .dragContainer(for: DragObject.self, selection: selected){ ids in
            dragItems(ids: ids)
        }
    }
    
    func dragItems(ids: [Int]) -> [DragObject] {
        return ids.map({ DragObject(index: $0)})
    }
}