I have a Diazo theme file based on html5boilerplate . A theme uses conditional comments on an element <html>to identify certain versions of Internet Explorer, for example.
<!doctype html>
<html class="no-js" lang="en">
However, when the theme is applied, Diazo seems to drop these conditional comments and only the last
stays in the final markup, producing something like
<!doctype html>
<html xmlns="http://www.w3.org/1999/xhtml" class="no-js" lang="en" xml:lang="en">
with unrivaled endif. Using conditional comments in a tag <html>(for example, inside <head>or below in a document) works fine.
Examples of theme files and rules that have this problem are available at
https://github.com/hexagonit/hexagonit.themeskel/blob/master/hexagonit/themeskel/templates/less_theme/+namespace_package+/+package+/theme_resources
plone.app.theming 1.0b8 KGS good-py.