Warnings:
Consider avoiding viewport values that prevent users from resizing documents.
The “banner” role is unnecessary for element “header”.
Section lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all sections.
Consider using the “h1” element as a top-level heading only (all “h1” elements are treated as top-level headings by many screen readers and other tools).
The “main” role is unnecessary for element “main”.
Article lacks heading. Consider using “h2”-“h6” elements to add identifying headings to all articles.
The “contentinfo” role is unnecessary for element “footer”.
The document is not mappable to XML 1.0 due to two consecutive hyphens in a comment.
Errors:
A “meta” element with an “http-equiv” attribute whose value is “X-UA-Compatible” must have a “content” attribute with the value “IE=edge”.
Bad value “ImageToolbar” for attribute “http-equiv” on element “meta”.
Attribute “href” not allowed on element “meta” at this point.
Element “meta” is missing one or more of the following attributes: “content”, “property”.
Bad value “https://fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,600,700,300italic,400italic,600italic,700italic|Ubuntu:300,400,500,700,300italic,400italic,500italic,700italic” for attribute “href” on element “link”: Illegal character in query: “|” is not allowed.
Element “div” not allowed as child of element “span” in this context. (Suppressing further errors from this subtree.)
Bad value “” for attribute “name” on element “button”: Must not be empty.
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Saw U+0000 in stream.
The “frameborder” attribute on the “iframe” element is obsolete. Use CSS instead.
Bad value “follow” for attribute “rel” on element “a”: The string “follow” is not a registered keyword.
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