This is not an option right now.
If you turn on the inventory option it will prevent customers from buying an option not in stock, but it will still display.
We are working on making this work the way you are requesting. When you have 1 option, its not so complicated, but when you have 2-3 options, it gets a little complicated. Ie. You may not have BLUE in small and Medium, but have it in Large. And so all options need to show in case they do want Blue Large. But as soon as they click Small then the blue option would have to disappear. Again you could have 5 options, 10 options, etc. and so when this change is made it must accommodate all possibilities and so this is why its still work in progress
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