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 784x84 [border: (2px solid #FF0000)]
        RenderInline {SPAN} at (0,0) size 108x56
          RenderInline {B} at (0,0) size 108x56
            RenderText {TEXT} at (14,14) size 108x28
              text run at (14,14) width 108: "xxxtestxxx"
            RenderBR {BR} at (0,0) size 0x0
            RenderText {TEXT} at (14,42) size 36x28
              text run at (14,42) width 36: "xxx"
            RenderBR {BR} at (0,0) size 0x0
        RenderText {TEXT} at (0,0) size 0x0
selection is CARET:
start:      position 3 of child 3 {TEXT} of child 1 {B} of child 2 {SPAN} of root {DIV}
upstream:   position 3 of child 3 {TEXT} of child 1 {B} of child 2 {SPAN} of root {DIV}
downstream: position 0 of child 4 {BR} of child 1 {B} of child 2 {SPAN} of root {DIV}
