Re: Conformance requirements on browsers

On 9/12/13 2:36 AM, Jukka K. Korpela wrote:
> Thanks. It indeed describes the effect of the attribute. I wonder if it
> is intentional that 11.2 does not refer to the description (in this or
> similar cases).

It is: people shouldn't be using these things.

> My question still applies to constructs that are only mentioned (and
> declared obsolete). At least <bgsound> is among them. Subsection 11.2
> says just “Use audio instead”, and it is mentioned in parsing rules
> (must be parsed as empty element), and it must use HTMLUnknownElement.
> So a little more than just mentioned, but with no description of the
> meaning or effect of the element

There is no meaning or effect.

> Does this mean that browsers are required to parse <bgsound> as an empty
> element and treat it as an HTMLUnknownElement object (which means just
> that in scripting you can detect it as HTMLUnknownElement but otherwise
> it’s HTMLElemen, right?) but can then do whatever they want with it? Or
> shall they otherwise ignore it?

They should otherwise ignore it.  There isn't supposed to be reading 
between the lines.

> Is IE non-conforming because it keeps supporting <bgsound>?

Yes, just like any UA that supports a tag that's not in the spec at all.

> We have an interesting company in 11.3.4: “The |blink
> <http://www.w3.org/TR/html5/obsolete.html#blink>|, |bgsound
> <http://www.w3.org/TR/html5/obsolete.html#bgsound>|, |isindex
> <http://www.w3.org/TR/html5/obsolete.html#isindex-0>|, |multicol
> <http://www.w3.org/TR/html5/obsolete.html#multicol>|, |nextid
> <http://www.w3.org/TR/html5/obsolete.html#nextid>|, |rb
> <http://www.w3.org/TR/html5/obsolete.html#rb>|, and |spacer
> <http://www.w3.org/TR/html5/obsolete.html#spacer>| elements must use the
> |HTMLUnknownElement
> <http://www.w3.org/TR/html5/dom.html#htmlunknownelement>| interface.” Is
> this meant to say something more than it formally says?

Not at all.  It means just what it says: 
Object.getPrototypeOf(document.createElement("isindex")) == 
HTMLUnknownElement.prototype.

Of course the same is true for <myfairlady> and <ohlookatthistag>.  ;)

> Does it mean that support to these should be dropped?

That depends on what the rest of the spec has to say about it.

 > <blink> is not supported by newest versions of any browser

Section 10.3.4 defines its behavior.  It's required by the spec to be 
supported to the extent that "text-decoration: blink" is supported.  For 
example, Gecko will compute the text-decoration style to "blink" (which 
is page-detectable and required by the spec) and then not blink the 
text, as allowed by 
http://www.w3.org/TR/CSS21/text.html#lining-striking-props

 > <bgsound> is now IE-only but still supported in IE 10

As far as I can tell, the spec calls for bgsound not making any sound, 
since it defines no special behavior for it.

> <isindex> is widely supported (though little used),

And is required to be supported by the spec.  See the "A start tag whose 
tag name is 'isindex'" bit in section 8.2.5.4.7 (the "in body" insertion 
mode section of the treebuilder) and the processing model described in 
http://www.w3.org/html/wg/drafts/html/master/forms.html#attr-fe-name and 
http://www.w3.org/html/wg/drafts/html/master/forms.html#application/x-www-form-urlencoded-encoding-algorithm

> <multicol> died with Netscape

The only UA conformance requirement I can see for <multicol>, apart from 
using HTMLUnknownElement as the interface, is section 10.3.10.

> <nextid> never had any browser support,

Indeed.  And the spec has no requirements for it other than the 
HTMLUnknownElement bit.  Same for <rb> and <spacer>.

-Boris

Received on Thursday, 12 September 2013 15:44:11 UTC