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macOS Safari v11.0 で次の条件をすべて満たす場合に要素の line-height 計算値がおかしくなる模様。場合によってはレイアウトが崩れる(例:Google AdSense のレポート画面など)。

1. 環境設定の「これより小さいフォントサイズを使わない」が有効である
2. CSS で要素の line-height プロパティに単位付きの値が指定されている
3. その要素の font-size 計算値が極端に小さい(0 など)



                div {
  background: #000;
  color: #fff;
  line-height: 16px;
  font-size: 0;