Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x600 [BFC] children: not-inline
    BlockContainer <body> at (8,8) content-size 784x48 children: inline
      frag 0 from BlockContainer start: 0, length: 0, rect: [8,8 61.1875x48] baseline: 36
      BlockContainer <div.ib> at (8,8) content-size 61.1875x48 inline-block [BFC] children: inline
        frag 0 from BlockContainer start: 0, length: 0, rect: [9,27 17.828125x22] baseline: 18
        frag 1 from TextNode start: 0, length: 1, rect: [28,30 8x17] baseline: 13.296875
            " "
        frag 2 from BlockContainer start: 0, length: 0, rect: [41,10 23.359375x44] baseline: 36
        TextNode <#text>
        BlockContainer <div.label> at (9,27) content-size 17.828125x22 inline-block [BFC] children: inline
          frag 0 from TextNode start: 0, length: 1, rect: [9,27 17.828125x22] baseline: 17
              "A"
          TextNode <#text>
        TextNode <#text>
        BlockContainer <button> at (41,10) content-size 23.359375x44 inline-block [BFC] children: not-inline
          BlockContainer <(anonymous)> at (41,10) content-size 23.359375x44 flex-container(column) [FFC] children: not-inline
            BlockContainer <(anonymous)> at (41,10) content-size 23.359375x44 flex-item [BFC] children: not-inline
              BlockContainer <(anonymous)> at (41,10) content-size 23.359375x0 children: inline
                TextNode <#text>
              BlockContainer <div> at (41,10) content-size 23.359375x44 children: inline
                frag 0 from TextNode start: 0, length: 1, rect: [41,10 23.359375x44] baseline: 34
                    "B"
                TextNode <#text>
              BlockContainer <(anonymous)> at (41,54) content-size 23.359375x0 children: inline
                TextNode <#text>
        TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x600]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x48]
      PaintableWithLines (BlockContainer<DIV>.ib) [8,8 61.1875x48]
        PaintableWithLines (BlockContainer<DIV>.label) [8,26 19.828125x24]
          TextPaintable (TextNode<#text>)
        TextPaintable (TextNode<#text>)
        PaintableWithLines (BlockContainer<BUTTON>) [36,8 33.359375x48]
          PaintableWithLines (BlockContainer(anonymous)) [41,10 23.359375x44]
            PaintableWithLines (BlockContainer(anonymous)) [41,10 23.359375x44]
              PaintableWithLines (BlockContainer(anonymous)) [41,10 23.359375x0]
              PaintableWithLines (BlockContainer<DIV>) [41,10 23.359375x44]
                TextPaintable (TextNode<#text>)
              PaintableWithLines (BlockContainer(anonymous)) [41,54 23.359375x0]
