JavaFX - How to create SnapShot/Screenshot of (invisble) WebView

Question

I want to create a SnapShot/Screenshot/Image from a WebView in JavaFX(8).
This WebView does not need to be visible (in my case).

My question:
Is

Answer 1

The class WebView contains the following function:

private boolean isTreeReallyVisible() {
    if (getScene() == null) {
        return false;
    }

    final Window window = getScene().getWindow();

    if (window == null) {
        return false;
    }

    boolean iconified = (window instanceof Stage) ? ((Stage)window).isIconified() : false;

    return impl_isTreeVisible()
           && window.isShowing()
           && window.getWidth() > 0
           && window.getHeight() > 0
           && !iconified;
}

As long as the function returns false, the rendering is blocked. So it might be quite tricky to get it to render. Normally, for snapshot you don't have to put the Node in the scene at all.