Filter to fix the Post Author Dropdown

// Filter to fix the Post Author Dropdown
add_filter('wp_dropdown_users', 'theme_post_author_override');
function theme_post_author_override($output)
{
  global $post, $user_ID;
  
  // return if this isn't the theme author override dropdown
  if (!preg_match('/post_author_override/', $output)) return $output;

  // return if we've already replaced the list (end recursion)
  if (preg_match ('/post_author_override_replaced/', $output)) return $output;

  // replacement call to wp_dropdown_users
  $output = wp_dropdown_users(array(
    'echo' => 0,
    'name' => 'post_author_override_replaced',
    'selected' => empty($post->ID) ? $user_ID : $post->post_author,
    'include_selected' => true
  ));

  // put the original name back
  $output = preg_replace('/post_author_override_replaced/', 'post_author_override', $output);

  return $output;
}