public BrowserHost(IntPtr rpHandle)
{
r_Handle = rpHandle;
BrowserService.Instance.Messages.SubscribeOnDispatcher(CommunicatorMessages.InvalidateArrange, _ => InvalidateArrange());
var rUIZoom = Preference.Instance.UI.Zoom.Value;
LayoutTransform = r_ScaleTransform = new ScaleTransform(1.0 / rUIZoom, 1.0 / rUIZoom);
Preference.Instance.UI.Zoom.Subscribe(r => r_ScaleTransform.ScaleX = r_ScaleTransform.ScaleY = 1.0 / r);
}