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  LayoutView at (0,0) size 800x600
layer at (0,0) size 800x472
  LayoutBlockFlow {HTML} at (0,0) size 800x472
    LayoutBlockFlow {BODY} at (8,16) size 784x446
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          text run at (0,0) width 746: "Tests that masked elements do not render until their mask images are fully loaded. You should not see any blue boxes below."
layer at (18,52) size 200x200 transparent
  LayoutBlockFlow {DIV} at (10,36) size 200x200 [bgcolor=#0000FF]
layer at (18,262) size 200x200 transparent
  LayoutBlockFlow {DIV} at (10,246) size 200x200 [bgcolor=#0000FF]