PageIdentity) where key is pageId * @param array &$thumbnails Output array (string=>SearchResultThumbnail|null) where key * is pageId and value is either a valid SearchResultThumbnail for given page or null * @param int|null $size size of thumbnail height and width in points */ public function onSearchResultProvideThumbnail( array $pageIdentities, &$thumbnails, ?int $size = null ); }