AccumulatedVisualContext Tree:
  [1] scroll_frame_id=1 (PaintableWithLines(BlockContainer<PRE>#out))
    [2] clip=[9,9 100x80]
      [3] scroll_frame_id=2 (PaintableWithLines(BlockContainer(anonymous)))
    [4] clip=[131,9 100x80]
      [5] scroll_frame_id=3 (PaintableWithLines(BlockContainer(anonymous)))

DisplayList:
SaveLayer@0
  CompositorWheelHitTestTarget@0 target_scroll_frame_index=0 rect=[0,0 800x600]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[0,0 800x103]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 784x82]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 784x82]
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[8,8 102x82]
  FillPath@1 path_bounding_rect=[8,8 102x82]
  CompositorWheelHitTestTarget@3 target_scroll_frame_index=0 rect=[9,9 150x120]
  FillRect@3 rect=[9,9 150x120] color=rgb(240, 128, 128)
  CompositorWheelHitTestTarget@1 target_scroll_frame_index=0 rect=[130,8 102x82]
  FillPath@1 path_bounding_rect=[130,8 102x82]
  CompositorWheelHitTestTarget@5 target_scroll_frame_index=0 rect=[131,9 150x120]
  FillRect@5 rect=[131,9 150x120] color=rgb(144, 238, 144)
  DrawGlyphRun@3 rect=[9,9 110x18] translation=[9,22.796875] color=rgb(0, 0, 0)
  DrawGlyphRun@5 rect=[131,9 119x18] translation=[131,22.796875] color=rgb(0, 0, 0)
Restore@0