It loads in 5 seconds for me but the interface has many bugs and fails to implement many behaviors of native elements: scrolling with mouse wheel doesn't work, using the elements with keyboard is impossible because it seems many of them doesn't even have a focused state. When trying to focus on elements with the Tab key it's messing up the whole scrollview because after that elements aren't working even with the mouse. Pressing the Enter key redirects to another page. So it's a pretty bad showcase and the other demos too have the same issues. (using Firefox on Windows)