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”.
The “main” role is unnecessary for element “main”.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
The first occurrence of ID “Twitter” was here.
Errors:
The “align” attribute on the “div” element is obsolete. Use CSS instead.
Element “h2” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “ul” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “div” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “form” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Element “hr” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Attribute “href” not allowed on element “span” at this point.
Element “p” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Bad value “presentation” for attribute “role” on element “video”.
Attribute “media” not allowed on element “source” at this point.
No “p” element in scope but a “p” end tag seen.
End tag “h3” seen, but there were open elements.
Unclosed element “span”.
End tag “a” violates nesting rules.
Saw “<?”. Probable cause: Attempt to use an XML processing instruction in HTML. (XML processing instructions are not supported in HTML.)
End tag “div” seen, but there were open elements.
Element “h3” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Stray end tag “span”.
Element “p” not allowed as child of element “a” in this context. (Suppressing further errors from this subtree.)
Duplicate ID “Twitter”.
Element “address” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
United States US