#xhtml validation

Sitecore has some handy and powerful validation capabilities. However, there is a validation rule that despite its good intent, will generally fail on newer websites.

If you use workflow in Sitecore and use the included Approve workflow step, it is setup to automatically validate for broken links and ensure that the content is correct XHTML. However, if you happen to be using HTML5 in your layout, say from HTML5 Boilerplate, this validation will fail. And there isn't much you can do about it. The typical error message for the failed validation tends to look like this:

What to do? Well aside from changing your template markup, not much. While there may be "better" ways to solve this, the simplest solution is to just remove the validation rule. The trouble is, finding and removing the rules isn't all that obvious - IMO. 

This can be found under Sitecore > System > Settings > Validation Rules > Global Rules. 

Select the "Global Rules" item and scroll down to the "Workflow" field. There you will find a rule in the right hand pane, called "Full Page XHtml" at the bottom of the list. Simply select this rule and remove it by pressing the left arrow button.