Import Entire Galleries From Any Webpage

add_filter(
  'fetch_gallery_supported_post_types',
  function ( $post_types ) {
    $post_types[] = 'product';
    $post_types[] = 'portfolio';
    return $post_types;
  }
);

add_filter(
  'fetch_gallery_upload_folder',
  function ( $folder, $post ) {
    return 'galleries/' . $folder;
  },
  10, 2
);

add_filter(
  'fetch_gallery_supported_extensions',
  function ( $extensions ) {
    $extensions[] = 'avif';
    $extensions[] = 'svg';
    return $extensions;
  }
);

add_action(
  'fetch_gallery_after_import',
  function ( $result, $url, $id ) {
    if ( $result->success ) {
      update_post_meta($result->id, '_meta', 'val');
    }
  },
  10, 3
);