On Tue, Aug 31, 2010 at 12:59 PM, Aryeh Gregor <[email protected]<simetrical%[email protected]> > wrote:
> On Tue, Aug 31, 2010 at 10:35 AM, Boris Zbarsky <[email protected]> wrote: > > You can't sniff in a toplevel browser window. Not the same way that > people > > are sniffing in <video>. It would break the web. > > How so? For the sake of argument, suppose you sniff only for known > binary video/audio types, and fall back to existing behavior if the > type isn't one of those (e.g., not video or audio). Do people do > things like link to MP3 files with incorrect MIME types and no > Content-Disposition, and expect them to download? If so, don't people > also link to MP3 files with correct MIME types and expect the same? I > don't see how sniffing vs. using MIME type makes a compatibility > difference here, since media support in browsers is so new -- surely > whatever bad thing happens, sniffing will make it happen more often, > at worst. > > What do Chrome and IE do here? > We use the incoming MIME type to determine whether we render the audio/video in the browser versus download. We would never want to execute multimedia sniffing code in the trusted/browser process so implementing sniffing for a top level browser window would involve sending the bytes to a sandboxed process for inspection first. This does have a side effect where a <video> may play fine on a page with a bogus MIME type (due to sniffing), but viewing the video URL in the browser itself would prompt a download. Andrew
