HTML5 validation will fail due to this meta tag:

<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">  

So, remove the <meta> tag from the document and add this to .htaccess (courtesy of html5 boilerplate)

<IfModule mod_headers.c>  
     Header set X-UA-Compatible "IE=Edge,chrome=1"
    <FilesMatch "\.(js|css|gif|png|jpe?g|pdf|xml|oga|ogg|m4a|ogv|mp4|m4v|webm|svg|svgz|eot|ttf|otf|woff|ico|webp|appcache|manifest|htc|crx|xpi|safariextz|vcf)$" >
      Header unset X-UA-Compatible
    </FilesMatch>
</IfModule>