line 1 column 1 - Warning: missing declaration line 6 column 10 - Warning: The summary attribute on the element is obsolete in HTML5 Info: Document content looks like HTML5 Tidy found 2 warnings and 0 errors! About HTML Tidy: https://github.com/htacg/tidy-html5 Bug reports and comments: https://github.com/htacg/tidy-html5/issues Official mailing list: https://lists.w3.org/Archives/Public/public-htacg/ Latest HTML specification: https://html.spec.whatwg.org/multipage/ Validate your HTML documents: https://validator.w3.org/nu/ Lobby your company to join the W3C: https://www.w3.org/Consortium Do you speak a language other than English, or a different variant of English? Consider helping us to localize HTML Tidy. For details please see https://github.com/htacg/tidy-html5/blob/master/README/LOCALIZE.md