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I am using Sitecore 8.2 in a Helix configuration and added some custom chrome placeholder styling that I found in the Professional Sitecore 8 Development book. The code works in that I can now see the custom chrome styling, but I am now receiving XHTML validation errors, whereas I wasn't getting these errors before.
I read that HTML5 tags may cause this kind of XHTML error, but the HTML5 tags I'm currently using were not causing this error before I added the chrome styling.
I also searched for the rendering IDs named in each error in the page source and they were each referring to the
<code></code> block that I believe contains the Json for each placeholder.
Does anyone know if the tag is not XHTML compliant? If it is, what can I do about this error?
Update: I've also discovered that when I check the Validation tool in the Home tab in the Proofing section from XP Editor, I have numerous warnings like "Warning: Could not find schema information for the element 'html'." and for every other common html tag.