We just upgraded our Mageto store to the latest version of 2.1.8..since we are keep getting following error.
Custom options with price type "percent" is not available for configurable product.
We're having the same issue, Magento 2.2.7. As result we can't save any changes on that field in the product, resulting that we need to delete the product and create a new one if a modification is required.
Any solution or suggestions?
Did you manage to sort this. I can't find a solution.