This is an archived snapshot of W3C's public bugzilla bug tracker, decommissioned in April 2019. Please see the home page for more details.
(Please note that this issue affects the w3.org website rather than the HTML+RDFa specification) The documented URI for the default XHTML vocabulary space is http://www.w3.org/1999/xhtml/vocab# For example, this page itself states: "This document describes the items that are available in the default XHTML vocabulary space: http://www.w3.org/1999/xhtml/vocab#." However, this URL is a permanent redirect to http://www.w3.org/1999/xhtml/vocab/# (note the trailing slash). This issue triggers some warnings on link validators, such as the one provided by the W3C itself. For an example, see this validation result: http://validator.w3.org/checklink?uri=http%3A%2F%2Fdemo.opensourcecms.com%2Fdrupal%2F&hide_type=all&depth=&check=Check As many third-party implementations already rely on the documented URI, the safest approach to solve the issue would be to make sure that the W3C website does not redirect when visiting http://www.w3.org/1999/xhtml/vocab#
The W3C server has been changed accordingly