Re: Validation of Facebook Code

On Sun, Sep 11, 2011 at 10:20 PM, Marvin Steppat
<> wrote:
> when I validated I noticed that the typical
> Facebook Markup
> <meta property="fb:page_id" content="17566831" />
> was flagged as illegal.


> That was a surprise because it is mandated this way by Facebook.

Are you talking about this page?

Major web companies like Facebook, along with many other sources of
developer influence, regularly suggest markup patterns that are

> Can somebody comment on the proposed best-practice to deal with this situation? Is there a way to reach
> full validity and be conformant with Facebook at the same time?

Not using your declared conformance target of XHTML 1.0 Strict.

It's not currently possible to serve markup as text/html that conforms
to W3C (X)HTML Recommendations and uses the pattern suggested by

W3C is working on a spec that would allow this markup pattern to
conform in text/html as HTML4 + RDFa, HTML5 + RDFa, or XHTML5 + RDFa:

As a working draft, this is a moving conformance target and may never
become a Recommendation. The W3C validator currently only supports
validating HTML4 + RDFa.

How you deal with this situation depends on what you're trying to get
out of validation. The following links might help you think about that

(My personal opinion is deviations from W3C Recommendations can be
useful, but should be deliberate not accidental. A good example of
useful non-conformance would be adding ARIA landmarks that improve
accessibility to a document that otherwise claims compatibility with
HTML 4.01. Consequently, the process of validation is more important
than the result of validity.)

Hope that helps.

Benjamin Hawkes-Lewis

Received on Friday, 16 September 2011 06:45:15 UTC