Why doesn't yarrow stack?

[D4wN]

I wasn't sure whether to put this here or in bugs. So I figured I'd ask here first. Why doesn't yarrow stack when you pick it?

[MissEvelyn]

You can get it to stack, but it is rather bugged.

If you have an existing stack in your inventory, here's how to make new yarrow stack with the existing:

• When harvesting or looting containers, make sure you click you on the yarrow in the container, without dragging it to your existing stack.
• The yarrrow is then looted as a new stack. Put this new stack back into the container.
• Click the new yarrow again in the container/loot window. This time it's looted into your existing stack.