I was testing the Stagger and Stupefy nodes for Drain Life, which grant a rather nice damage multiplier against Bosses/Rares for single target damage along with a stun proc. On paper it seemed strong but one of those nodes adds a cooldown to Drain Life. I found that getting stunned made the ability unusable as you get stunned, it goes on cooldown, and now you have nothing.
I noticed channeled spells have an effect listed on LE Tools that says +1 Stun Immunity. Not sure what this is supposed to be, if it’s a leftover mechanic that doesn’t exist anymore, or is just bugged for Drain Life. If it’s not a bug I think it definitely needs to be a thing when a channeled spell has a cooldown.