Can I change the windowed mode icon, the one on the title bar and task bar, can’t find about it on org.lwjgl.opengl.Display API, am I miss it?
Also I have searched all the forums but no luck 
Right now… there isn’t a way to do that (afaik). Windowed mode was put in as a debug thingy in first place, which would explain that.
Yes, it’s a debug thingy, but it would be cool when using an undecorated window as a splash screen before loading a game. Besides, when a user minimizes the fullscreen window, not having an icon there would look kind of amateurish…
Anyway, you’ll have to nag Elias, Matzon or Cas for this. (Please do so! ;D)
It’s on the to-do list.
Cas 
Yay
Thanks it will be great to have this!