plugin=diff is not implemented.
http://yellow.ribbon.to/~tuotehhou/index.php?%2BC%EF%BC%83%2B%E5%8B%95%E7%9A%84%E3%81%AB%E3%83%A1%E3%82%BD%E3%83%83%E3%83%89%E3%81%AE%E5%91%BC%E5%87%BA
plugin=diff is not implemented.