layer at (0,0) size 800x600
  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 (3,4) size 12x12
      RenderText {#text} at (18,0) size 218x18
        text run at (18,0) width 218: "This checkbox should be checked."
