Example
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of parent/child attribute
Create attribute Color&size.
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Element type: - selectbox. Here you need to add option values like XS, S, L...
3. Then create new child attribute Color. Set Attribute Parent: Color&Size.
Here you need add Add option values like white, black, red..etc. Element type: - selectbox.
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Now if you go to product edit page click to add a new Color&Size global attribute to editable the product.
5. Add Option's values to Product
Then add option value like black:XS black:S white:L white:XS red:S red:L or any other combination of product you have to sell.
In storefront, customer can choose combined option value
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