Try going to http://www.mkdocs.org/ and put your mouse to the right of "Host anywhere". You'd expect to see the permalink for that heading, but instead, the permalink for "Great themes available" shows up. This can be pretty annoying, since it makes it harder to click on the permalink; if you go a pixel too far to the right, you have to move your mouse back over the text itself, and then back again to the permalink.

As far as I can tell, this is because of the following code: https://github.com/mkdocs/mkdocs/blob/master/mkdocs/themes/mkdocs/css/base.css#L43-L49. I gather that it's there to work around the existence of the header so that anchor links go to the right spot. I'd argue that the old Javascript way was better, unless someone can figure out a way to trick CSS into handling the hover state better.