Test structured clone permutations in IndexedDB with shared memories. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". indexedDB = self.indexedDB || self.webkitIndexedDB || self.mozIndexedDB || self.msIndexedDB || self.OIndexedDB; indexedDB.deleteDatabase(dbname) indexedDB.open(dbname) store = db.createObjectStore('storeName') This index is not used, but evaluating key path on each put() call will exercise (de)serialization: store.createIndex('indexName', 'dummyKeyPath') Running tests... Test shared WebAssembly.Memory transaction = db.transaction('storeName', 'readwrite') store = transaction.objectStore('storeName') PASS store.put(memory, 'key') threw exception DataCloneError: The object can not be cloned.. PASS successfullyParsed is true TEST COMPLETE