anchor.diff:    @override
     Future<Uint8List> restore() async {
       final transaction =
  -    _database.transactionStore(_objectStoreName, 'readonly');
  +        _database.transactionStore(_objectStoreName, 'readonly');
       final store = transaction.objectStore(_objectStoreName);
   
       final result = await store.getObject(name) as Blob /*?*/;
  
positive.code:   /// IndexedDB based implementation. This parameter can be turned off for
    /// applications that never used the local storage implementation as a small
    /// performance improvement.
    ///
    /// However, older browsers might not support IndexedDB.
    @experimental
  
negative.code:   @override
    Future<void> store(Uint8List data) async {
      final transaction =
          _database.transactionStore(_objectStoreName, 'readwrite');
      final store = transaction.objectStore(_objectStoreName);
  
      await store.put(Blob([data]), name);
  