Now it is possible to assign a default purchasing category for a supplier. This can be used as a fallback method to resolve the purchasing category, when the category cannot be for example solved by mapping the product's UNSPSC code to a purchasing category.
The default category can be set in Data Management > Purchasing categories.
Multiple suppliers can have the same default purchasing category, but a single supplier can only have one default category.
This functionality is only available in Integrated shopping experience.