How do you get Spirit Essence from Lost Spirits?

[Dan_al_Thor]

So going around Elderglen Woods during the Soulfaring festival I got a toast pop-up that lost spirits were a useful resource for divine favor or spirit essence. I know you can use the arcane spell final rites to ferry the soul and get divine favor, but how do you get spirit essence?

I thought that perhaps the absorb spell could be used for this but after making several attempts, nothing dropped. Is this a bug or am I not using the right method?

[Neversalimus]

Using absorb spell doesn't drop for me either looks like this spell is bugged, to drop spirit essences just make sure you kill thing with necromancy spells.

[Dan_al_Thor]

Right as of current patch that seems to be the only way to get Spirit essence unless I am missing something