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  RenderView at (0,0) size 800x600
layer at (0,0) size 800x600
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    RenderBody {BODY} at (8,8) size 784x584
      RenderBlock (floating) {DIV} at (0,0) size 50x400 [bgcolor=#008000]
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            text run at (2,0) width 76: "Hello world"
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            text run at (0,0) width 139: "Some fieldset content."