HTML Checking for Large Sites

Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.

Bad value “https://www.w3.org/1999/xlink” for the attribute “xmlns:link” (only “http://www.w3.org/1999/xlink” permitted here).

The only permitted value for the xmlns:link attribute is http://www.w3.org/1999/xlink.

Although using https in the URL looks like it’s going to be more secure, in fact this URL is not used to connect it to, only to declare the namespace.

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