layer at (0,0) size 820x585
  RenderCanvas at (0,0) size 800x585
layer at (0,0) size 820x585
  RenderBlock {HTML} at (0,0) size 800x585
    RenderBody {BODY} at (8,64) size 784x457
      RenderBlock {DIV} at (64,0) size 748x196 [border: (50px solid #FF0000)]
        RenderInline {SPAN} at (0,0) size 32x28
          RenderText {TEXT} at (74,84) size 32x48
            text run at (74,84) width 32: "foo"
        RenderText {TEXT} at (106,84) size 40x48
          text run at (106,84) width 40: " baz"
selection is CARET:
start:      position 3 of child 1 {TEXT} of child 2 {SPAN} of root {DIV}
upstream:   position 3 of child 1 {TEXT} of child 2 {SPAN} of root {DIV}
downstream: position 0 of child 4 {TEXT} of root {DIV}