I am getting the above validation error in response to the following line in my HTML:
<meta http-equiv="X-XRDS-Location" content="http://www.example.com/wp-content/plugins/socialauth-wp/hybridauth/index.php?get=openid_xrds" />
I use WordPress social auth plugin, that automatically adds this line to the head of every page.
I am not sure what this line does to the site but it throws a validation error.
What does the meta line does to the site, is it mandatory?
I gone through the question
Get rid of âBad value X-XRDS-Location for attribute http-equiv on XHTML element meta.â in XHTML5 validation, but I’m not sure how to register it.
My answer to the linked question applies here, too:
If you use HTML5, you may only use the following values for the
http-equiv
attribute:X-XRDS-Location
is not defined/registered, so HTML5 doesnât allow to use it.I guess the linked XRDS document is used to discover your OpenID service provider. Or for Oauth, etc..
An alternative may be to send the HTTP header
X-XRDS-Location
. If you send it, you could remove themeta
element (unless some data consumers only look for the occurence in the HTML, which would be a bad practice).