How can I add the base URL to 404.html using Vite?

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In Vite, you can add the base URL to the 404.html file by including the following code at the top of the file:

<script>
  const baseUrl = import.meta.env.BASE_URL;
  const url = new URL(window.location.href);
  url.pathname = baseUrl + '/404.html';
  window.location = url.href;
</script>

This code gets the current base URL from the Vite environment variable import.meta.env.BASE_URL, then modifies the current URL and redirects the user to the 404 page with the updated base URL.