Source of HTTP Content-Language header

Hi!

The W3 Validator reports a content language warning for my www.f3historic..com<http://www.f3historic.com> website. It says that

The value of the HTTP Content-Language header is "fr" but it will be ignored because the html start tag has lang="en".

I checked all files and couldn't find any reference to the content language header being set to French. Could you please modify the W3 Validator such that it shows the location of the content language header, just like it does for the HTML start tag.

Best regards, Christoph

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