3491119 - Custom business catalog is not available for selection in Custom Catalog Extensions app - SAP S/4HANA Cloud

You have developed a Custom Business Catalog in the context of Developer Extensibility (ABAP Environment) and you want to use it in a Custom Catalog Extension. However, the created catalog is not available for selection. 

SAP S/4HANA Cloud Public Edition 

1. In Development Tenant, create a Custom Business Catalog in Development Tenant as per Creating a Business Catalog | SAP Help Portal.
2. In Customizing Tenant, access the Custom Catalog Extensions application and try to create a Custom Catalog Extension as per How to Add Custom Catalog Extensions | SAP Help Portal with the created catalog.

The creation of a Business Catalog in ABAP Environment is only relevant when you create a Custom Application in the context of Developer Extensibility and want to provide authorization to this custom app.

The Custom Catalog Extensions app is relevant in the context of Key User Extensibility, it is responsible for providing authorization to custom applications created with Key User Extensibility through Standard Business Catalogs.

Therefore, it is not supported to use Custom Business Catalogs in Custom Catalog Extensions app. 

Custom Catalog Extensions | SAP Help Portal

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