-if ( isset( $_SERVER['QUERY_STRING'] )
- && preg_match( '/\.[^\\/:*?"<>|%]+(#|\?|$)/i', $_SERVER['QUERY_STRING'] ) )
+$dotPos = strrpos( $path, '.' );
+$whitelist = array();
+if ( $dotPos !== false ) {
+ $whitelist[] = substr( $path, $dotPos + 1 );
+}
+if ( !$wgRequest->checkUrlExtension( $whitelist ) )