[whatwg] First or last Content-Type header?

Philip Taylor excors+whatwg at gmail.com
Wed Jun 3 00:36:10 PDT 2009

On Wed, Jun 3, 2009 at 12:51 AM, Aryeh Gregor <Simetrical+w3c at gmail.com> wrote:
> Sending a text/plain Content-Type will not prevent any
> (default-configured) version of IE from interpreting the file as HTML,
> even if it's the *only* Content-Type header sent.  This is why Adam
> Barth said "The only browser that uses the first header more or less
> ignores it anyway."  This apparently isn't fixed even in IE8: it
> insists on still upsniffing text/plain to text/html unless you use the
> nonstandard header "Content-Type: text/plain; authoritative=true;".

- it's "X-Content-Type-Options: nosniff" now (and is used a bit in
practice - it's on about 0.1% of pages from
http://www.dotnetdotcom.org/, though about half of them are owned by
Google or Microsoft).

Philip Taylor
excors at gmail.com

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