Slingshot Ammo Loading on a Mac?

[Nattattack]

I can't for the life of me figure out how to load ammo into the slingshot. I know you're supposed to have rocks and then click on them and right click the slingshot but everytime I do it nothing happens? I'm playing on a Mac so I don't know if this is a problem for other Mac users? Is there another way to do it?

[TheOnlyCharlieMoon]

I have the same problem in Mac. When I try to load a slingshot it simply switches what I’m holding. No idea how to fix it though, sorry. Maybe it’s a bug or something we just are both missing.

[Nakos]

Place the slingshot in your inventory. Place the stones in your inventory.

Left-click on the stones to pick up the stack.
Right-click on the slingshot to load the stones into the slingshot.

(Yes, I am using a Mac, although I believe it should be the same for both Mac and PC).