3498228 - Fiori Launchpad Designer (FLPD) is not showing the custom catalogs created in the Fiori Launchpad Application Manager (FLPAM) or Content Manager (FLPCM)

After creating a custom technical catalog using the FLPAM (Application Manager), the content of the catalog is not accessible and/or cannot be managed in the FLPD (Launchpad Designer).
Instead, it shows a red error icon and/or no tiles assigned. 

PS: The same applies for custom business catalogs created in the FLPCM (Content Manager). 

• SAP Fiori Launchpad 2020 and later versions

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