According to html5 the closed tags for thead, tbody, tfoot are optional. But doclint generate an error if these tags are absent
https://www.w3.org/TR/html51/syntax.html#optional-tags.
A thead element’s end tag may be omitted if the thead element is immediately followed by a tbody or tfoot element.
A tbody element’s end tag may be omitted if the tbody element is immediately followed by a tbody or tfoot element, or if there is no more content in the parent element.
A tfoot element’s end tag may be omitted if the tfoot element is immediately followed by a tbody element, or if there is no more content in the parent element.
https://www.w3.org/TR/html51/syntax.html#optional-tags.
A thead element’s end tag may be omitted if the thead element is immediately followed by a tbody or tfoot element.
A tbody element’s end tag may be omitted if the tbody element is immediately followed by a tbody or tfoot element, or if there is no more content in the parent element.
A tfoot element’s end tag may be omitted if the tfoot element is immediately followed by a tbody element, or if there is no more content in the parent element.