             
             self.dataSource.insert(event)
             self.collectionView.performBatchUpdates({
-                self.collectionView.insertItems(at: [IndexPath(item: self.dataSource.count - 1, section: 0)])
+                self.collectionView.animator().insertItems(at: [IndexPath(item: self.dataSource.count - 1, section: 0)])
             }, completionHandler: { b in
                 guard shouldScroll else { return }
                 self.collectionView.animator().scrollToItems(at: [self.collectionView.indexPathForLastItem()],

                        let t = (0..<self.dataSource.count).map {
                            IndexPath(item: $0, section: 0)
                        }
                        self.collectionView.insertItems(at: Set(t))
                    }, completionHandler: { b in
                        group.animate(duration: 0.5)
                        self.collectionView.animator().scrollToItems(at: [self.collectionView.indexPathForLastItem()],

        c.dataSource = self
        c.delegate = self
        c.backgroundColors = [.clear]
        c.selectionType = .one
        
        c.registerForDraggedTypes([.png, .string, .filePromise])
        c.setDraggingSourceOperationMask([.copy], forLocal: true)
        c.setDraggingSourceOperationMask([.copy], forLocal: false)
        
        let l = NSCollectionViewFlowLayout()//NSCollectionViewListLayout()
        //l.globalSections = (32, 0)
