Errors:
Element “title” not allowed as child of element “head” in this context. (Suppressing further errors from this subtree.)
Bad value “https://api.w.org/” for attribute “rel” on element “link”: The string “https://api.w.org/” is not a registered keyword.
Bad value “” for attribute “src” on element “img”: Must be non-empty.
Duplicate attribute “rel”.
The “frameborder” attribute on the “iframe” element is obsolete. Use CSS instead.
The “scrolling” attribute on the “iframe” element is obsolete. Use CSS instead.
The “allowtransparency” attribute on the “iframe” element is obsolete. Use CSS instead.
Element “g:plusone” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
End tag “div” seen, but there were open elements.
Unclosed element “span”.
Attribute “alt” not allowed on element “input” at this point.
End tag “li” seen, but there were open elements.
Unclosed element “div”.
Bad value “100%” for attribute “width” on element “iframe”: Expected a digit but saw “%” instead.
Stray end tag “a”.
The “center” element is obsolete. Use CSS instead.
Duplicate ID “copyright”.
Warnings:
Consider avoiding viewport values that prevent users from resizing documents.
Empty heading.
Element name “g:plusone” cannot be represented as XML 1.0.
The “border” attribute is obsolete. Consider specifying “img { border: 0; }” in CSS instead.
The first occurrence of ID “copyright” was here.
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