Viewport <#document> at [0,0] [0+0+0 800 0+0+0] [0+0+0 600 0+0+0] [BFC] children: not-inline
  BlockContainer <html> at [0,0] [0+0+0 800 0+0+0] [0+0+0 18 0+0+0] [BFC] children: inline
    InlineNode <span> at [0,0] [0+0+0 51.75 0+0+0] [0+0+0 18 0+0+0]
      frag 0 from TextNode start: 0, length: 7, rect: [0,0 51.75x18] baseline: 13.796875
          "whf :^)"
      TextNode <#text> (not painted)

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x18]
    PaintableWithLines (InlineNode<SPAN>) [0,0 51.75x18]
      TextPaintable (TextNode<#text>)

SC for Viewport<#document> [0,0 800x600] [children: 1] (z-index: auto)
 SC for BlockContainer<HTML> [0,0 800x18] [children: 0] (z-index: auto)
