Errors:
A document must not include both a “meta” element with an “http-equiv” attribute whose value is “content-type”, and a “meta” element with a “charset” attribute.
Bad value “https://api.w.org/” for attribute “rel” on element “link”: The string “https://api.w.org/” is not a registered keyword.
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Bad value “100%” for attribute “width” on element “iframe”: Expected a digit but saw “%” instead.
The “frameborder” attribute on the “iframe” element is obsolete. Use CSS instead.
The “scrolling” attribute on the “iframe” element is obsolete. Use CSS instead.
Stray end tag “a”.
End tag “br”.
No space between attributes.
Quote “"” in attribute name. Probable cause: Matching quote missing somewhere earlier.
Bad value “100px” for attribute “width” on element “img”: Expected a digit but saw “p” instead.
Bad value “50px style=” for attribute “height” on element “img”: Expected a digit but saw “p” instead.
Attribute “align:center"” not allowed on element “img” at this point.
Element “script” must not have attribute “charset” unless attribute “src” is also specified.
Attribute “alt” not allowed on element “a” at this point.
Warnings:
Consider avoiding viewport values that prevent users from resizing documents.
The “navigation” role is unnecessary for element “nav”.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.
Attribute “align:center"” is not serializable as XML 1.0.
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