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JavaScript error

SyntaxError

The JavaScript exception "new keyword cannot be used with an optional chain" occurs when the constructor of a new expression is an optional chain, or if there's an optional chain between the constructor and the parenthesized list of arguments.

Reference entryJavaScriptFetched
This is a reference entry from MDN Web Docs. A full explanation with fixes has not been written yet.

The error messages

SyntaxError: Invalid optional chain from new expression (V8-based)
As listed by MDN Web Docs
SyntaxError: new keyword cannot be used with an optional chain (Firefox)
As listed by MDN Web Docs
SyntaxError: Cannot call constructor in an optional chain. (Safari)
As listed by MDN Web Docs

Details

Category
SyntaxError
Severity
error
Runtime
both

Related errors

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Source: MDN Web Docs. Data fetched 2026-09-25T01:48:37.273Z.