HTML Checking for Large Sites

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

Obsolete doctype. Expected “<!DOCTYPE html>”.

Rocket Validator checks HTML on your sites using the latest version of W3C Validator Nu HTML Checker, which is intended for HTML5 documents.

The page scanned is using an obsolete doctype, instead of the expected <!DOCTYPE html>.

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Related W3C validator issues