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JS
JavaScript error

Warning

The JavaScript warning "-file- is being assigned a //# sourceMappingURL, but already has one." occurs when a source map has been specified more than once for a given JavaScript source.

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

The error message

Warning: -file- is being assigned a //# sourceMappingURL, but already has one.
As listed by MDN Web Docs

Details

Category
A warning. JavaScript execution won't be halted
Severity
warning
Runtime
both

Related errors

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