[whatwg] HTML5 video element - default to fallback in cases where UA can't play format

[Gregory Maxwell]

On Tue, Oct 27, 2009 at 7:40 PM, Kit Grose <kit at iqmultimedia.com.au> wrote:
[snip]
> I expected (incorrectly, in this case) that if I only produced one
> source element (an MP4), Firefox would drop down to use the fallback
> content, as it does if I include an object element for a format not
> supported (for example, if I include a QuickTime object and QT is not
[snip]

Please see the list archives:
http://www.mail-archive.com/whatwg@lists.whatwg.org/msg16092.html

In short, there are corner cases which make this untenable. E.g. what
happens when you have JS doing brilliant canplaytype magic, but also
provide tag-interior fallbacks for clients which may not even have JS?
 They'll fire off and start before your JS has a chance to do its
canplaytype magic.


Of course, "standards-compliant HTML/XHTML using CSS and Javascript as
required by the design", as your products are described, is pretty
meaningless when its applied to sites no more compatible than the bad
old "Works best in IE" days, only it's now Apple™ and Adobe™.  I urge
you to consider the values of an open and interoperable web against
the costs, and I hope you are informing your customer(s) about any
long term licensing fees for the formats chosen for their site.