Bootstrap 3 hidden-* doesn't work on intermediate window sizes-CodePudding

Bootstrap 3 classes hidden-* seems doesn't work properly on some window sizes. I suppose that this code must hide text forever:

<!doctype html>
<html>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">

<body>
  <div class="hidden-xs hidden-sm hidden-md hidden-lg">hidden</div>
</body>
</html>

But on some window width (in very narrow intervals) it's shown. Checked in Chrome, Firefox, Edge. Firefox extension "Bootstrap - Responsible Helper" show always "LG" when text is visible.