Vlad Yes Safari does that too but not as bad as Orion, which should be inline with safari regarding the stutter/lags as it is based on webkit. Whereas Safari felt a lot smoother than Orion when scrolling.
And the video you showed, there are hiccups when scrolling on both safari and Orion but they are very close now.
My main concern is that it shouldn't happen altogether. It only ruins the experience of a really amazing browser that I really want to use but these stutter and lags just ruin it.