AccumulatedVisualContext Tree:
  [0] transform=[1,0,0,1,0,0] origin=(0,0) (ViewportPaintable(Viewport<#document>))
    [1] scroll_frame_id=1 (PaintableWithLines(BlockContainer<PRE>#out))
      [2] clip=[8,8 200x200]
        [3] effects=[opacity=0.5]
          [6] transform=[1,0,0,1,20,20] origin=(8,8) (SVGPathPaintable(SVGGeometryBox<rect>))

DisplayList:
SaveLayer@0
  CompositorWheelHitTestTarget@0 target_scroll_frame_index=0 rect=[0,0 800x600]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[0,0 800x221]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 784x200]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 784x200]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 200x200]
  FillPath@6 path_bounding_rect=[8,8 100x100]
Restore@0

