HTML Checking for Large Sites

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

The value used in the target property of an <a> element has been identified as a keyword because it starts with an underscore _, but it’s not a valid keyword.

Values starting with an underscore for the target property are used for reserved keywords like _blank, _self, _parent or _top.

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Related W3C validator issues