Our DPI Aware application no longer works correctly while running on Windows 8.1 Preview. It appears that with Windows 8.1 Preview, the WebBrowser control does not respect the hosting application's DPI Awareness setting. Changing the Manfest to "Per Monitor Hight DPI Aware" or "High DPI Aware" has no impact on the browser content.
When the DPI is set to "Larger" in Control Panel -> Appearance and Personalization -> Display "Change Size of all items", the browser control will have Horizontal and Vertical Scroll Bars that can not be removed via CSS, HTML or SetHostFlags(DOCHOSTUIFLAG_SCROLL_NO).
For some reason, the control will now set OLECMDID_OPTICAL_ZOOM to the users DPI.