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  RenderView at (0,0) size 800x600
layer at (0,0) size 800x600
  RenderBlock {HTML} at (0,0) size 800x600
    RenderBody {BODY} at (8,8) size 784x584
      RenderBlock {INPUT} at (4,3) size 13x13
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        text run at (20,1) width 209: "This checkbox should be checked."