CSS comment inside of @supports incorrect CSS output

[zachleat]

Input:

@supports ( box-shadow: none ) {
    /* Shadow on first body column */
    .sizechart {
        position: relative;
    }
}

libsass 3.3.6

@supports (box-shadow: none) { {
    /* Shadow on first body column */
  }
  .sizechart {
    position: relative;
  }
}

Sass 3.4.21

@supports (box-shadow: none) {
  /* Shadow on first body column */
  .sizechart {
    position: relative;
  }
}

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