Ah. I don’t believe I saw that documented anywhere. While the API documentation is fairly extensive, and has links to seful jsFiddles and such, if a control has HTML requirements (like a div for the window title), that doesn’t seem to be covered.
Just because an example might show one, the example and/or documentation doesn’t indicate what’s necessary vs optional.
On this topic, I also frequently see disparities between the documentation in the Demo tab and the documentation under the ‘Documentation’ tab. Generally, it seems that the Demos documentation is more up to date.