src/vs/workbench/contrib/notebook/common/model/notebookTextModel.ts/NotebookEventEmitter/isDirtyEvent
class NotebookEventEmitter:	isDirtyEvent() {
		for (const e of this._eventQueue) {
			for (let i = 0; i < e.rawEvents.length; i++) {
				if (!e.rawEvents[i].transient) {
					return true;
				}
			}
		}

		return false;
	}