For some reason it fires hypeDocument.goToTimeInTimelineNamed() only at the end of the scroll, no intermediate steps.
When you scroll in IE with a mouse ScrollAmount is changing per pixel but the argument of the function gets only end position. therefore the animation jumps from point to point.
Everything works fine in Edge, Chrome, mobile or in IE if scrolled with sidebar.
Is there anything I should know about hypeDocument.goToTimeInTimelineNamed()? What am I missing?