3x-ui/frontend/.storybook/preview-head.html

<script>
  if (typeof navigator !== 'undefined' && (!navigator.language || navigator.language.includes('@'))) {
    Object.defineProperty(navigator, 'language', { value: 'en-US', configurable: true });
  }
  if (localStorage.getItem('dark-mode') === null) localStorage.setItem('dark-mode', 'false');
  if (localStorage.getItem('isUltraDarkThemeEnabled') === null) {
    localStorage.setItem('isUltraDarkThemeEnabled', 'false');
  }
</script>