sousa-gecko/testing/web-platform/tests/css/css-fonts/lang-attribute-affects-rendering-ref.html

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <style>
    * { font-size: 50px }

    @font-face {
      font-family: test-font-family;
      src: url(/fonts/Lato-Medium.ttf);
    }

    div { font-family: test-font-family; }
  </style>
</head>
<body>
  `lang="en"` should render ligatures, `lang="tr"` not.
  <div lang="tr">fi</div>
</body>
</html>