Dye vials don't seem mixable in the inventory by clicking and dragging. When I click and drag a dye vial, the others light up and highlight when I drag the vial over them, but releasing doesn't seem to do anything. I get no feedback or anything and the vials stay separate colours. I've tried with many combinations of yellow, red, blue, green, orange and black which I feel should make a colour.

1. Have two (or more) different coloured dye vials in your inventory

2. Click and drag one of them onto the other

3. Nothing happens.