I suppose one could create a scrolling view of the webpage, using JavaScript in an embedded media type. I’ll leave that up to others to experiment with.
Meanwhile, certainly you can hike the webpage up in steps using the following method.
In the region’s timeline, place multiple webpage media types. Set their Options to “Manual Position”, then set the Offset Top for each to successively larger values, from 0 to however much you need until the bottom of the page is visible in the last one.