[xwiki-devs] [Proposal] Break the XHTML validity to catch HTML5 validy

Hello developers. I am working on making the HTML 5 code of XWiki valid. But in some places, I cannot do it without breaking the XHTML validity (which Colibri still uses, but this skin is going to be deprecated). Example: in XHTML 1.0, the attribute target="_blank", for links, is forbidden. In XWiki, we have "fixed" this by using the attribute rel="_blank" instead, and then we have a javascript snippet that dynamically adds the target="_blank" attribute to these links [1]. So the code is valid until the javascript is loaded, which is enough to pass our validation tests. This is not very clean, since the target="_blank" was forbidden by the w3c because they think it should be the user choice to open a link in a new window or not. But nobody respects this, and that is why it is no longer forbidden in HTML5. The problem we have, is that the value "_blank" is not authorized anymore for the "rel" attribute of the links in HTML5. So I propose to remove our workaround, which is useless and prohibited for HTML5. As a consequence, we would lose the XHTML validity (which is actually the case when javascript is loaded anyway). WDYT? Guillaume [1] The code that looks for ref="_blank": https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwi…