Facebook & Open Graph’s XML Nameservers Within the opening <html> tag, the Facebook and Open Graph nameservers need to be included to tell your browser and other parsers that it can expect tags other than HTML:
Attention in classroom
Facebook & Open Graph’s XML Nameservers Within the opening <html> tag, the Facebook and Open Graph nameservers need to be included to tell your browser and other parsers that it can expect tags other than HTML: