Scrolling has velocity (in Chrome)

Hello,

Not in Safari nor Firefox, but in Chrome, when scrolling, it seems to have too much “velocity” or I don’t know how to call it. But I just scroll a little bit and the screen scrolls a lot. This seems to happen as well with your theme’s demo page. But if I change theme then it’s gone.

What is it and how can it be turned back to normal please?

Thanks!