This is a reference entry from MDN Web Docs. A full explanation with fixes has not been written yet.
URIError: URI malformed (V8-based)
URIError: malformed URI sequence (Firefox)
URIError: String contained an illegal UTF-16 sequence. (Safari)
- Category
- URIError
- Severity
- error
- Runtime
- both
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Source: MDN Web Docs. Data fetched 2026-09-25T01:48:37.274Z.