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In section 4.12.1 it says that the href attribute on a link element 'has to be a valid non-empty URL' (i.e. not potentially surrounded by spaces), in 4.2.4 is says this it 'must contain a valid non-empty URL potentially surrounded by spaces'. 4.12.1: http://dev.w3.org/html5/spec/Overview.html#hyperlink-elements 4.2.4: http://dev.w3.org/html5/spec/Overview.html#the-link-element
EDITOR'S RESPONSE: This is an Editor's Response to your comment. If you are satisfied with this response, please change the state of this bug to CLOSED. If you have additional information and would like the editor to reconsider, please reopen this bug. If you would like to escalate the issue to the full HTML Working Group, please add the TrackerRequest keyword to this bug, and suggest title and text for the tracker issue; or you may create a tracker issue yourself, if you are able to do so. For more details, see this document: http://dev.w3.org/html5/decision-policy/decision-policy.html Status: Did Not Understand Request Change Description: no spec change Rationale: The section in question has been somewhat revamped. Does your problem still exist? I can't find it anymore, but I may have fixed it in those recent edits.
Yes, it looks like the href requirement was removed from the links section so it's only specified in one place now.