layer at (0,0) size 800x600
  RenderCanvas 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 {DIV} at (0,0) size 784x56 [border: (2px solid #FF0000)]
        RenderInline {SPAN} at (0,0) size 177x28
          RenderText {TEXT} at (14,14) size 36x28
            text run at (14,14) width 36: "xxx"
          RenderInline {B} at (0,0) size 141x28
            RenderText {TEXT} at (50,14) size 36x28
              text run at (50,14) width 36: "xxx"
            RenderInline {I} at (0,0) size 105x28
              RenderText {TEXT} at (86,14) size 36x28
                text run at (86,14) width 36: "xxx"
              RenderInline {SPAN} at (0,0) size 69x28
                RenderText {TEXT} at (122,14) size 33x28
                  text run at (122,14) width 33: "xxx"
                RenderInline {SPAN} at (0,0) size 36x28
                  RenderText {TEXT} at (155,14) size 36x28
                    text run at (155,14) width 36: "xxx"
          RenderText {TEXT} at (0,0) size 0x0
          RenderInline {SPAN} at (0,0) size 0x0
          RenderText {TEXT} at (0,0) size 0x0
selection is CARET:
start:      position 3 of child 1 {TEXT} of child 2 {SPAN} of child 2 {SPAN} of child 2 {I} of child 2 {B} of child 1 {SPAN} of root {DIV}
upstream:   position 3 of child 1 {TEXT} of child 2 {SPAN} of child 2 {SPAN} of child 2 {I} of child 2 {B} of child 1 {SPAN} of root {DIV}
downstream: position 1 of child 5 {TEXT} of child 1 {SPAN} of root {DIV}