Porting an application from Qt Webkit to Qt WebEngine. The web page displays application data, not HTTP content, and all navigation is handled internally, by overloading QWebEnginePage::acceptNavigationRequest().

Qt Webkit QWebPage had a way to get and restore the current scroll position through

somepos = mainFrame()->scrollPosition(),mainFrame()
mainFrame()->setScrollPosition(somepos)

QWebEngine page now (5.7) has a scrollposition property, but it is readonly as far as I can see from the documentation.

Being able to set the scroll position is important so that the page position can be restored when the user moves back in the history.