I am using an HTML5 document with <nav> tags http://www.w3schools.com/html5/tag_nav.asp. This document is also being used as the source for an EPUB document. I am therefore using the <nav> tag's epub:type attribute to conform with the upcoming EPUB3 specification.

so <nav epub:type="toc">nav stuff here...</nav>

Currently, when building with PrinceXML 8, when I try to convert this HTML document with prince, I get the following error:

prince: builds/html/book.html:34: error: Namespace prefix epub for type on nav is not defined

Is there any way that you can allow these types of attributes for the prince build, or perhaps create a flag to ignore attributes in standard HTML5 tags?

Thanks for the great work!

Is the document well-formed XHTML? If it is, then I would recommend using the XML parser, with "-i xml", or by renaming the file to have .xhtml or .xml extension.

Isn't supposed to support all the valid HTML5 tags?!
Actually when I try to print an HTML5 with PHP extension, I get the following errors:

Seems like doesn't recognize any new HTML5 tags!

https://richstyle.org

Our current HTML parser doesn't recognise HTML5 tags, so it issues warnings, but it still parses them and they should still work. The next version of Prince will have a new HTML5 parser that does not issue warnings for these tags.