I once worked on my project and stopped it. Yesterday i was browsing through the backup of my old project and found this buffer. I think it could be useful for someone.
Thanks to @Trance for coding. I modified abit and adapted to l2jfrozen. Unfortunately i can't find the HTML anymore, so you have to create your own.
Here you go.
What it does? Watch here.
Create a file in gameserver/model/actor/instance called L2NpcBufferInstance.java