Watch the video till the end. Have you noticed how the touch and the movement of the slider are not synchronized? In practice it is even more noticeable, the finger reaches the end of the screen without completing the slider movement

I think this is because dragging doesn't start until the slop threshold is exceeded, but the slider doesn't compensate for the slop once it starts moving, like most UI controls. Did you file a bug?

Yep, Zach is right about the slop 🙂 Please file a bug. We need to chase the finger after slop has passed probably

I will file a bug in the next hours. Thank you for answering.