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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 784x576
      RenderBlock {P} at (0,0) size 784x18
        RenderText {#text} at (0,0) size 318x17
          text run at (0,0) width 318: "This tests that attachments have a custom renderer."
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        RenderInline {ATTACHMENT} at (0,0) size 0x0
        RenderText {#text} at (0,0) size 0x0