Posted by Alan J. Flavell on 09/30/05 02:34

On Thu, 29 Sep 2005, Jim Higson wrote:

> Browsers tend to compensate for bad HTML more than bad CSS because the de
> facto rules on what bad HTML to accept were created in the 'wild west'
> early days of the web, when browser makers regularly disregarded the specs.

There's something in what you say, but CSS is older than you seem to
be making out...

> CSS support was added later,

Well, yes, to the popular browsers: but there had been experimental
implementations of an early version for quite some time already
(overshadowed by the unfortunate stampede to Netscape's presentational
quasi-HTML from which we're now suffering the legacy); the CSS mandate
to ignore constructions which the client does not understand, goes
back to the early days of the CSS language - and you already know what
motivated it, because you mention it below.

MSIE 3.x, as usual for MS, happily disregarded the mandate, and (IIRC)
interpreted em units (which it did not understand) as px units (which
it thought it did), with the obvious consequences.

> Specifically, disregarding invalid CSS rules is good because it makes future
> compatability easier.

Just so!

> If the CSS2 browser started trying to guess what
> all the unrecognised rules meant there'd be chaos.

Indeed there was!

cheers

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