LyXHTML doc doesn't pass validation

[Lorenzo Bertini]

Running a very simple LyXHTML doc (a section with a few paragraphs) 
against this validator https://validator.w3.org/check reports some 
errors, I don't really know if we care or not:

1. value of attribute "dir" cannot be "auto"; must be one of "ltr", "rtl"
2. element "section" undefined

Is this a problem? I just wanted to check if I could use the <figure> 
tag but its not part of the specification.

Best regards,

Lorenzo (lynx)