AccumulatedVisualContext Tree:
  [0] transform=[1,0,0,1,0,0] origin=(0,0) (ViewportPaintable(Viewport<#document>))
    [1] scroll (PaintableWithLines(BlockContainer<PRE>#out))

DisplayList:
SaveLayer@0
  CompositorWheelHitTestTarget@0 target_scroll_node_index=0 rect=[0,0 800x600]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[0,0 800x121]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[8,8 784x100]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[8,8 784x20]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[8,28 40x40]
  FillPath@1 path_bounding_rect=[8,28 40x40]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[8,68 40x40]
  FillPath@1 path_bounding_rect=[8,68 40x40]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[8,8 40x20]
  FillPath@1 path_bounding_rect=[8,8 40x20]
  CompositorWheelHitTestTarget@1 target_scroll_node_index=0 rect=[48,8 40x20]
  FillPath@1 path_bounding_rect=[48,8 40x20]
Restore@0

