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  RenderView at (0,0) size 800x600
layer at (0,0) size 800x0
  RenderBlock {HTML} at (0,0) size 800x0
layer at (0,0) size 800x20
  RenderBlock (positioned) {HEAD} at (0,0) size 800x20
layer at (0,0) size 800x20
  RenderBody {BODY} at (0,0) size 800x20 [color=#000080]
    RenderBlock {P} at (0,0) size 800x20
      RenderText {#text} at (0,0) size 280x19
        text run at (0,0) width 280: "This line should have a yellow background."