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 (2,4) size 12x12
      RenderText {#text} at (16,0) size 220x18
        text run at (16,0) width 220: "This checkbox should be checked."