Nice work. There is a tiny glitch on first load on windows with chrome. The content shakes in order to fit screen. It may be about hiding the default scroller.
yep, I see that now, you are right. Probably it would be better to disable the default scroller for all the devices and then: on Mac/Ubuntu/iOS/Android we activate the system scroll (which looks better) and on Windows, we activate the perfectScrollbar library. We will do an update soon.