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 (4,3) size 17x16
      RenderText {#text} at (25,3) size 218x17
        text run at (25,3) width 218: "This checkbox should be checked."