line 25 column 5 - Info: detected autonomous custom tag <new-tag>; will treat as block level
line 13 column 3 - Warning: <li> attribute "is" lacks value
line 14 column 3 - Warning: <li> attribute "is" lacks value
line 15 column 3 - Warning: <li> attribute "is" has invalid value "custom_element"
line 16 column 3 - Warning: <li> attribute "is" has invalid value "custom-element me_too"
line 22 column 5 - Warning: <jets-pizza> attribute "is" not allowed for autonomous custom tags.
line 25 column 5 - Warning: <new-tag> attribute "is" not allowed for autonomous custom tags.
line 19 column 5 - Warning: <pizzerias> is not approved by W3C
Info: Document content looks like HTML5
Tidy found 7 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
