I believe I came across the idea in castoptions (or something similar) in the cosmos package. But the only way to get that is by running the whole cosmos package, which I'm not interested in doing (I'd rather run one set of libraries at once, really).
Interestingly I got so used to it I thought it was the default behavior of the ui, and now really miss it, now that I've switched away from cosmos to ace and ace2 in the interests of memory/cpu efficiency.
If there's an alternative or a potentiality of this being coded into a mod I'd love to hear of it.
It's a neat little selfcast addon. But I had a question with it:
Is it within the scope of the addon to cast offensive spells on your targets target if you're targetting a friendly player?
So if I were healing a player, but wanted to cast an attack spell on his target it would automatically assist the player when I cast the spell. And visa versa for targetting enemies; just assist that target to get the target of your buff/heal.