layer at (0,0) size 800x600
  RenderView at (0,0) size 800x600
layer at (0,0) size 800x52
  RenderBlock {test} at (0,0) size 800x52
    RenderBlock {p} at (0,16) size 800x20
      RenderText {#text} at (0,0) size 478x19
        text run at (0,0) width 478: "Try selecting some text in this document. It should be have a green background."