ShapePath fillColor and strokeColor become wrong when Item windows is lost

Shape/ShapePath fillColor and strokeColor seem to 'come back' to a previous color when Shape lose the link to 'window' (when one of its parent is null -> onWindowChanged).

The problem should be arround 'Shape.GeometryRenderer' because there is no bug using the software renderer (QMLSCENE_DEVICE=softwarecontext).

Steps to reproduce :

1) start the main.qml (attached)

2) click on first checkbox -> stroke color change to red

3) click on 2nd checkbox -> the draw is not visible

4) click again on 2nd checkbox -> the draw come back visible

But ShapePath stroke come back to 'green' (and should be 'red' like the rectangle and the label text)