Vaillant-group.com W3C HTML Markup Validation
HTML markup errors and warnings
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Errors:
Attribute “aria-role” not allowed on element “a” at this point.
Bad value “content” for attribute “role” on element “main”.
Bad value “tabpanel” for attribute “role” on element “li”.
Bad value “https://twitter.com/intent/tweet?url=http://www.vaillant-group.com/&t=Vaillant Group - Taking care of a better climate” for attribute “href” on element “a”: Illegal character in query: space is not allowed.
Attribute “target” not allowed on element “div” at this point.
Bad value “complementary” for attribute “role” on element “footer”.
The “aria-labelledby” attribute must point to an element in the same document.
The “itemprop” attribute was specified, but the element is not a property of any item.
Warnings:
The document is not mappable to XML 1.0 due to two consecutive hyphens in a comment.
The “navigation” role is unnecessary for element “nav”.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
Empty heading.
United Kingdom GB