Problem with Shulkers.

Shulkers keep shooting projectiles at each other

I dont know if mojang meant to make shulkers hate each other.

So i spawned a couple of Shulkers

When i flied away where shulkers cant see me.

They just keep shooting their projectiles to eachother

So i made them Invulnerable with "

{Invulnerable:1}

so they cant hit each other.

But they still getting damage even theyre Invulnerable