diff --git a/dfindexeddb/indexeddb/chromium/record.py b/dfindexeddb/indexeddb/chromium/record.py
index e24ca3b..841035b 100644
--- a/dfindexeddb/indexeddb/chromium/record.py
+++ b/dfindexeddb/indexeddb/chromium/record.py
@@ -659,25 +659,26 @@ class GlobalMetaDataKey(BaseIndexedDBKey):
 
   METADATA_TYPE_TO_CLASS = {
       definitions.GlobalMetadataKeyType
-          .SCHEMA_VERSION: SchemaVersionKey,
+          .ACTIVE_BLOB_JOURNAL: ActiveBlobJournalKey,
       definitions.GlobalMetadataKeyType
-          .MAX_DATABASE_ID: MaxDatabaseIdKey,
+        .DATA_VERSION: DataVersionKey,
       definitions.GlobalMetadataKeyType
-          .DATA_VERSION: DataVersionKey,
+          .DATABASE_FREE_LIST: DatabaseFreeListKey,
       definitions.GlobalMetadataKeyType
-          .RECOVERY_BLOB_JOURNAL: RecoveryBlobJournalKey,
+          .DATABASE_NAME: DatabaseNameKey,
       definitions.GlobalMetadataKeyType
-          .ACTIVE_BLOB_JOURNAL: ActiveBlobJournalKey,
+          .EARLIEST_COMPACTION_TIME: EarliestCompactionTimeKey,
       definitions.GlobalMetadataKeyType
           .EARLIEST_SWEEP: EarliestSweepKey,
       definitions.GlobalMetadataKeyType
-          .EARLIEST_COMPACTION_TIME: EarliestCompactionTimeKey,
+          .MAX_DATABASE_ID: MaxDatabaseIdKey,
       definitions.GlobalMetadataKeyType
-          .SCOPES_PREFIX: ScopesPrefixKey,
+          .RECOVERY_BLOB_JOURNAL: RecoveryBlobJournalKey,
       definitions.GlobalMetadataKeyType
-          .DATABASE_FREE_LIST: DatabaseFreeListKey,
+          .SCHEMA_VERSION: SchemaVersionKey,
       definitions.GlobalMetadataKeyType
-          .DATABASE_NAME: DatabaseNameKey}
+          .SCOPES_PREFIX: ScopesPrefixKey,
+  }
 
   def DecodeValue(self, decoder: utils.LevelDBDecoder) -> Any:
     """Decodes the value from the current position of the LevelDBDecoder.
@@ -690,16 +691,16 @@ def DecodeValue(self, decoder: utils.LevelDBDecoder) -> Any:
   def FromDecoder(
       cls, decoder: utils.LevelDBDecoder, key_prefix: KeyPrefix,
       base_offset: int = 0
-  ) -> Union[Type[ActiveBlobJournalKey],
-             Type[DataVersionKey],
-             Type[DatabaseFreeListKey],
-             Type[DatabaseNameKey],
-             Type[EarliestSweepKey],
-             Type[EarliestCompactionTimeKey],
-             Type[MaxDatabaseIdKey],
-             Type[RecoveryBlobJournalKey],
-             Type[SchemaVersionKey],
-             Type[ScopesPrefixKey]]:
+  ) -> Union[ActiveBlobJournalKey,
+             DataVersionKey,
+             DatabaseFreeListKey,
+             DatabaseNameKey,
+             EarliestSweepKey,
+             EarliestCompactionTimeKey,
+             MaxDatabaseIdKey,
+             RecoveryBlobJournalKey,
+             SchemaVersionKey,
+             ScopesPrefixKey]:
     """Decodes the global metadata key.
 
     Raises:
@@ -712,7 +713,7 @@ def FromDecoder(
     if not key_class:
       raise errors.ParserError('Unknown metadata key type')
     return key_class.FromDecoder(
-        decoder, key_prefix, base_offset)  #pytype: disable=bad-return-type
+        decoder, key_prefix, base_offset)
 
 
 @dataclass
@@ -1058,7 +1059,6 @@ def FromDecoder(
     """Decodes the exists entry key."""
     offset = decoder.stream.tell()
     encoded_user_key = IDBKey.FromDecoder(decoder, offset)
-
     return cls(
         offset=base_offset + offset,
         key_prefix=key_prefix, encoded_user_key=encoded_user_key)
@@ -1145,13 +1145,13 @@ class IndexedDbKey(BaseIndexedDBKey):
   """
 
   METADATA_TYPE_TO_CLASS = {
-      definitions.KeyPrefixType.GLOBAL_METADATA: GlobalMetaDataKey,
+      definitions.KeyPrefixType.BLOB_ENTRY: BlobEntryKey,
       definitions.KeyPrefixType.DATABASE_METADATA: DatabaseMetaDataKey,
-      definitions.KeyPrefixType.OBJECT_STORE_DATA: ObjectStoreDataKey,
       definitions.KeyPrefixType.EXISTS_ENTRY: ExistsEntryKey,
+      definitions.KeyPrefixType.GLOBAL_METADATA: GlobalMetaDataKey,
+      definitions.KeyPrefixType.INVALID_TYPE: None,
       definitions.KeyPrefixType.INDEX_DATA: IndexDataKey,
-      definitions.KeyPrefixType.BLOB_ENTRY: BlobEntryKey,
-      definitions.KeyPrefixType.INVALID_TYPE: None
+      definitions.KeyPrefixType.OBJECT_STORE_DATA: ObjectStoreDataKey,
   }
 
   def DecodeValue(self, decoder: utils.LevelDBDecoder) -> Any:
@@ -1167,9 +1167,9 @@ def FromDecoder(
       decoder: utils.LevelDBDecoder,
       key_prefix: KeyPrefix,
       base_offset: int = 0
-  ) -> Union[Type[DatabaseMetaDataKey], Type[ExistsEntryKey],
-             Type[BlobEntryKey], Type[GlobalMetaDataKey],
-             Type[IndexDataKey], Type[ObjectStoreDataKey]]:
+  ) -> Union[DatabaseMetaDataKey, ExistsEntryKey,
+             BlobEntryKey, GlobalMetaDataKey,
+             IndexDataKey, ObjectStoreDataKey]:
     """Decodes the IndexedDB key."""
     key_type = key_prefix.GetKeyPrefixType()
     key_class = cls.METADATA_TYPE_TO_CLASS.get(key_type)
diff --git a/dfindexeddb/indexeddb/chromium/v8.py b/dfindexeddb/indexeddb/chromium/v8.py
index f882a18..e06b0eb 100644
--- a/dfindexeddb/indexeddb/chromium/v8.py
+++ b/dfindexeddb/indexeddb/chromium/v8.py
@@ -375,7 +375,7 @@ def ReadSparseJSArray(self) -> types.JSArray:
       js_array.values.append(types.Undefined())
 
     num_properties = self._ReadJSObjectProperties(
-        js_array.__dict__, definitions.V8SerializationTag.END_SPARSE_JS_ARRAY)
+        js_array.properties, definitions.V8SerializationTag.END_SPARSE_JS_ARRAY)
     _, expected_num_properties = self.decoder.DecodeUint32Varint()
     _, expected_length = self.decoder.DecodeUint32Varint()