The shaking of the happy ghast

When you bring a snowball close to the upper part of the Happy Ghast, it will start to tremble and will only stop when you switch to another item.

I'm not sure if this counts as a bug.

拿雪球靠近善魂接近顶部的位置时，善魂会发生抖动直到切换到别的物品时才会停下来

我不知道这是不是BUG特性