Check that transactions that may overlap complete properly. 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) prepareDatabase(): db = event.target.result store = db.createObjectStore('store') store.put('value', 'key') runParallelTransactions(): db = event.target.result transaction1 = db.transaction('store', 'readonly') transaction2 = db.transaction('store', 'readonly') transaction1GetSuccess = 0 transaction2GetSuccess = 0 onTransactionComplete(): first transaction complete, still waiting... onTransactionComplete(): PASS transaction1GetSuccess is non-zero. PASS transaction2GetSuccess is non-zero. db.close() PASS successfullyParsed is true TEST COMPLETE