[IndexedDB] Can IDBTransaction.oncomplete callback be used as active state?

Transaction is active as long as I send request from the IDBRequest
callback. Is there any other way to prevent committing?

If there any way to detect transaction active flag?

I expect IDBTransaction.oncomplete callback can be used to flag inactive
state, but it is not according to my few test. Transaction is already
inactive and cannot be use even before receiving oncomplete callback.