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+0 324 0+0+0] [BFC] children: not-inline
    BlockContainer <body> at [8,8] [8+0+0 784 0+0+8] [8+0+0 308 0+0+8] children: not-inline
      Box <div.my-container.column> at [9,9] flex-container(column) [0+1+0 782 0+1+0] [0+1+0 306 0+1+0] [FFC] children: not-inline
        BlockContainer <(anonymous)> (not painted) [BFC] children: inline
          TextNode <#text> (not painted)
        BlockContainer <div.box> at [10,10] flex-item [0+1+0 100 0+1+0] [0+1+0 100 0+1+0] [BFC] children: inline
          frag 0 from TextNode start: 0, length: 1, rect: [10,10 6.34375x18] baseline: 13.796875
              "1"
          TextNode <#text> (not painted)
        BlockContainer <(anonymous)> (not painted) [BFC] children: inline
          TextNode <#text> (not painted)
        BlockContainer <div.box> at [10,112] flex-item [0+1+0 100 0+1+0] [0+1+0 100 0+1+0] [BFC] children: inline
          frag 0 from TextNode start: 0, length: 1, rect: [10,112 8.8125x18] baseline: 13.796875
              "2"
          TextNode <#text> (not painted)
        BlockContainer <(anonymous)> (not painted) [BFC] children: inline
          TextNode <#text> (not painted)
        BlockContainer <div.box> at [10,214] flex-item [0+1+0 100 0+1+0] [0+1+0 100 0+1+0] [BFC] children: inline
          frag 0 from TextNode start: 0, length: 1, rect: [10,214 9.09375x18] baseline: 13.796875
              "3"
          TextNode <#text> (not painted)
        BlockContainer <(anonymous)> (not painted) [BFC] children: inline
          TextNode <#text> (not painted)
      BlockContainer <(anonymous)> at [8,316] [0+0+0 784 0+0+0] [0+0+0 0 0+0+0] children: inline
        TextNode <#text> (not painted)

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x324]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x308]
      PaintableBox (Box<DIV>.my-container.column) [8,8 784x308]
        PaintableWithLines (BlockContainer<DIV>.box) [9,9 102x102]
          TextPaintable (TextNode<#text>)
        PaintableWithLines (BlockContainer<DIV>.box) [9,111 102x102]
          TextPaintable (TextNode<#text>)
        PaintableWithLines (BlockContainer<DIV>.box) [9,213 102x102]
          TextPaintable (TextNode<#text>)
      PaintableWithLines (BlockContainer(anonymous)) [8,316 784x0]

SC for Viewport<#document> [0,0 800x600] [children: 1] (z-index: auto)
 SC for BlockContainer<HTML> [0,0 800x324] [children: 0] (z-index: auto)
