line 1 column 1 - Warning: missing <!DOCTYPE> declaration
line 19 column 5 - Warning: missing <tr>
line 29 column 11 - Error: discarding unexpected </form>
line 29 column 18 - Error: discarding unexpected </td>
line 25 column 3 - Warning: missing </form>
line 6 column 3 - Warning: The summary attribute on the <table> element is obsolete in HTML5
line 13 column 3 - Warning: The summary attribute on the <table> element is obsolete in HTML5
line 18 column 5 - Warning: The summary attribute on the <table> element is obsolete in HTML5
line 26 column 5 - Warning: The summary attribute on the <table> element is obsolete in HTML5
Info: Document content looks like HTML5
7 warnings, 2 errors were found!

You may need to move one or both of the <form> and </form>
tags. HTML elements should be properly nested and form elements
are no exception. For instance you should not place the <form>
in one table cell and the </form> in another. If the <form> is
placed before a table, the </form> cannot be placed inside the
table! Note that one form can't be nested inside another!

About HTML Tidy: https://github.com/htacg/tidy-html5
Bug reports and comments: https://github.com/htacg/tidy-html5/issues
Or send questions and comments to: https://lists.w3.org/Archives/Public/public-htacg/
Latest HTML specification: http://dev.w3.org/html5/spec-author-view/
Validate your HTML documents: http://validator.w3.org/nu/
Lobby your company to join the W3C: http://www.w3.org/Consortium