Re: Conformance requirements on browsers

2013-09-12 18:43, Boris Zbarsky wrote:
> 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.

That’s what I thought, but it makes life more difficult to people 
working with legacy code (either old code or old software that generates 
old-style code). There are good reasons not to rewrite legacy code or 
patch (fix) it, as long as it works, but some changes may be necessary. 
So it is relevant to to have convenient access to information that tells 
which of the obsolete features actually work or are required to work in 
browsers.

When working with old code (maintaining and modifying, not rewriting 
it), you can leave e.g. <font> tags as they are, but you need to 
consider what to do with <basefont> – if you know that no support is 
required any more, or that support is now forbidden (and, as a matter of 
fact, support has been dropped from modern browsers, including IE 10). 
Currently, both <font> and <basefont> are listed as obsolete, and you 
need to scan through the Rendering section to see their real status, 
regarding requirements on browsers.

> 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.
I’d still like to see where this is stated. User agents are required to 
process elements and attributes in certain ways, but where does the spec 
forbid them from doing anything additional with them?

As I tried to point out, the spec strongly discourages vendor 
extensions, but it does not forbid them. In 2.2.3, a document using 
vendor extensions is declared non-conforming. Wouldn’t this be the place 
to say that a user agent supporting vendor extensions is non-conforming 
too, if this is what is meant? It says: “New element names should not be 
created.” By saying “should” and not “shall”, this seems to mean that a 
browser supporting an element not mentioned in the spec at all may be 
conforming.

It sounds illogical that a browser is not allowed to support <bgsound> 
but is allowed to support <backgroundsound>.

-- 
Yucca, http://www.cs.tut.fi/~jkorpela/

Received on Friday, 13 September 2013 08:57:28 UTC