chromium/third_party/blink/renderer/core/testing/data/display_mode.html

<!doctype html>
<html>
<style>
@media all and (display-mode: minimal-ui) {
  #regular {
    display: none;
  }
}
@media not all and (display-mode: minimal-ui) {
  #minimal {
    display: none;
  }
}
</style>
<body>

<div id="minimal">minimal-ui</div>

<div id="regular">regular-ui</div>

</body>
</html>