src/vs/workbench/contrib/notebook/browser/viewModel/notebookViewModelImpl.ts/NotebookViewModel/lastNotebookEditResource
class NotebookViewModel:	get lastNotebookEditResource(): URI | null {
		if (this._lastNotebookEditResource.length) {
			return this._lastNotebookEditResource[this._lastNotebookEditResource.length - 1];
		}
		return null;
	}