The attribute used on `<html>` is not allowed at this point in time.

# How do I fix this ?

Remove the attribute from your code. If you want to add attributes for storing data you may use the html5 `data-` attributes.

`<element data-good-property="value">`

Some attributes that you can use are:

* `<html lang="en-US">`
* `<html dir="rtl">`

# Resources

* [HTML attributes](http://www.tutorialspoint.com/html/html_attributes.htm)
