Deprecated code

[hkirsman]

I see that the module is D9 compatible but found this from the code:

// Define file_uri_scheme if it does not exist, it's required by realpath().
// The function file_uri_scheme is deprecated and will be removed in 9.0.0.
if (!function_exists('file_uri_scheme')) {
  function file_uri_scheme($uri) {
    return \Drupal::service('file_system')->uriScheme($uri);
  }
}

While the function fixes file_uri_scheme, there's also this change in core:

In Drupal 9 \Drupal::service('file_system')->uriScheme() has been replaced with \Drupal::service('stream_wrapper_manager')->getScheme()

[hkirsman]

Here's one possible solution from Image resize filter module:

  // Once Drupal 8.7.x is unsupported remove this IF statement.
  if (floatval(\Drupal::VERSION) >= 8.8) {
    $info['scheme'] = \Drupal::service('stream_wrapper_manager')->getScheme($uri);
  }
  else {
    $info['scheme'] = \Drupal::service('file_system')->uriScheme($uri);
  }