DOMError has been removed from the DOM standard in favor of DOMException, and the Indexed DB draft spec has been updated to use DOMException for error attributes. The error attribute on IDBRequest and IDBTransaction will now return DOMException instances instead of DOMError instances. Both types have 'name' and 'message' properties, so code that tests properties (e.g. request.error.name) or does logging (e.g. transaction.error.message) will be unaffected.
Samples: https://developer.mozilla.org/en-US/docs/Web/API/IDBRequest/error https://developer.mozilla.org/en-US/docs/Web/API/IDBTransaction/error