pandoc-2.1.2: test/command/4281.md

```
% pandoc -t native
:::: {.a}
- ::: {.b}
  text
  :::
  ::: {.c}
  text
  :::
::::
^D
[Div ("",["a"],[])
 [BulletList
  [[Div ("",["b"],[])
    [Para [Str "text"]]
   ,Div ("",["c"],[])
    [Para [Str "text"]]]]]]
```