line 29 column 1 - Info: detected autonomous custom tag ; will treat as inline line 31 column 1 - Info: detected autonomous custom tag ; will treat as inline line 17 column 1 - Warning: is not approved by W3C line 21 column 1 - Warning: is not approved by W3C line 29 column 1 - Warning: is not approved by W3C line 31 column 1 - Warning: is not approved by W3C Info: Doctype given is "-//W3C//DTD HTML 4.01 Transitional//EN" Info: Document content looks like HTML Proprietary Tidy found 4 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