src/vs/workbench/contrib/notebook/browser/controller/coreActions.ts/NotebookCellAction/isCellActionContext
class NotebookCellAction:	protected isCellActionContext(context?: unknown): context is INotebookCellActionContext {
		return !!context && !!(context as INotebookCellActionContext).notebookEditor && !!(context as INotebookCellActionContext).cell;
	}