demo · v130

IndexedDB large-value error inspector

Write and read large Blobs to a real IDB store. The log captures whatever request.error surfaces. In v130, large-value read failures carry a descriptive DOMException name and message instead of a generic UnknownError.

log

the code

const req = store.get("big");
req.onerror = (ev) => {
  const err = ev.target.error;          // DOMException
  console.log(err.name);                 // pre-v130: "UnknownError"
                                         // v130+: "DataError" / "DataCloneError" / etc
  console.log(err.message);              // detailed message rather than the generic one
};

see also