The Howlitzer skulls no longer explode in your face if you keep swording them after they die, instead there is a moment where the skull is invincible, swording will knock it back, and it and also cannot hurt you. Then it does an attack animation with purple glow and flies at you.
It can still explode any time after the skull's the attack animation, but it's your own fault if you are still swording it that long after the skull appears. ^_^
Just wanted to let everyone know about this. :P
Ah yes, I forgot to add this to the patch notes. Thanks for discovering it!