src/vs/workbench/contrib/notebook/browser/view/renderers/webviewPreloads.ts/MarkupCell/addEventListeners
class MarkupCell:		private addEventListeners() {
			this.element.addEventListener('dblclick', () => {
				postNotebookMessage<webviewMessages.IToggleMarkupPreviewMessage>('toggleMarkupPreview', { cellId: this.id });
			});

			this.element.addEventListener('click', e => {
				postNotebookMessage<webviewMessages.IClickMarkupCellMessage>('clickMarkupCell', {
					cellId: this.id,
					altKey: e.altKey,
					ctrlKey: e.ctrlKey,
					metaKey: e.metaKey,
					shiftKey: e.shiftKey,
				});
			});

			this.element.addEventListener('contextmenu', e => {
				postNotebookMessage<webviewMessages.IContextMenuMarkupCellMessage>('contextMenuMarkupCell', {
					cellId: this.id,
					clientX: e.clientX,
					clientY: e.clientY,
				});
			});

			this.element.addEventListener('mouseenter', () => {
				postNotebookMessage<webviewMessages.IMouseEnterMarkupCellMessage>('mouseEnterMarkupCell', { cellId: this.id });
			});

			this.element.addEventListener('mouseleave', () => {
				postNotebookMessage<webviewMessages.IMouseLeaveMarkupCellMessage>('mouseLeaveMarkupCell', { cellId: this.id });
			});

			this.element.addEventListener('dragstart', e => {
				markupCellDragManager.startDrag(e, this.id);
			});

			this.element.addEventListener('drag', e => {
				markupCellDragManager.updateDrag(e, this.id);
			});

			this.element.addEventListener('dragend', e => {
				markupCellDragManager.endDrag(e, this.id);
			});
		}