layer at (0,0) size 800x600
  RenderCanvas at (0,0) size 800x600
layer at (0,0) size 800x204
  RenderBlock {HTML} at (0,0) size 800x204
    RenderBody {BODY} at (0,0) size 800x204
      RenderPartObject {IFRAME} at (0,0) size 500x100
        layer at (0,0) size 485x100
          RenderCanvas at (0,0) size 485x100
        layer at (0,0) size 485x76
          RenderBlock {HTML} at (0,0) size 485x76
            RenderBody {BODY} at (8,8) size 469x52
              RenderBlock {P} at (0,0) size 469x18
                RenderText {TEXT} at (0,0) size 110x18
                  text run at (0,0) width 110: "This is some text."
              RenderBlock {P} at (0,34) size 469x18
                RenderText {TEXT} at (0,0) size 147x18
                  text run at (0,0) width 147: "This text is underneath."
      RenderText {TEXT} at (500,86) size 4x18
        text run at (500,86) width 4: " "
      RenderPartObject {OBJECT} at (0,104) size 500x100
        layer at (0,0) size 485x100
          RenderCanvas at (0,0) size 485x100
        layer at (0,0) size 485x76
          RenderBlock {HTML} at (0,0) size 485x76
            RenderBody {BODY} at (8,8) size 469x52
              RenderBlock {P} at (0,0) size 469x18
                RenderText {TEXT} at (0,0) size 110x18
                  text run at (0,0) width 110: "This is some text."
              RenderBlock {P} at (0,34) size 469x18
                RenderText {TEXT} at (0,0) size 147x18
                  text run at (0,0) width 147: "This text is underneath."