src/vs/workbench/api/browser/mainThreadNotebookDocuments.ts/MainThreadNotebookDocuments/handleNotebooksRemoved
class MainThreadNotebookDocuments:	handleNotebooksRemoved(uris: URI[]): void {
		for (const uri of uris) {
			this._documentEventListenersMapping.get(uri)?.dispose();
			this._documentEventListenersMapping.delete(uri);
		}
	}