plugin=diff is not implemented.
http://yellow.ribbon.to/~tuotehhou/index.php?%2BCSS%2Bimg%E8%A6%AA%E3%81%AE%E3%82%B5%E3%82%A4%E3%82%BA%E3%81%AB%E3%82%88%E3%82%8B%E8%87%AA%E8%AA%BF%E6%95%B4
plugin=diff is not implemented.