Features like preserve scroll position and fixed elements only work with the viewport set on the artboards in XD at the moment, and not any scrolling added by the prototype viewer in the browser. I would like it to be activated also when scrolling is added by the prototype viewer in the browser.

Please see this prototype for the problem: https://xd.adobe.com/view/267a66a3-c9fa-45f6-6997-0aa455e7b854-504b/?fullscreen&hints=off

Thanks