src/vs/workbench/contrib/notebook/browser/view/cellParts/cellDnd.ts/CellDragAndDropController/onCellDragover
class CellDragAndDropController:	private onCellDragover(event: CellDragEvent): void {
		if (!event.browserEvent.dataTransfer) {
			return;
		}

		if (!this.currentDraggedCell) {
			event.browserEvent.dataTransfer.dropEffect = 'none';
			return;
		}

		if (this.isScrolling || this.currentDraggedCell === event.draggedOverCell) {
			this.setInsertIndicatorVisibility(false);
			return;
		}

		const dropDirection = this.getDropInsertDirection(event.dragPosRatio);
		const insertionIndicatorAbsolutePos = dropDirection === 'above' ? event.cellTop : event.cellTop + event.cellHeight;
		this.updateInsertIndicator(dropDirection, insertionIndicatorAbsolutePos);
	}