Reading Living Atlas layers anonymously (no authentication) is done using the Standalone Server source type but the 3.21.2 package errors. This is a publicly shared service you can try:
https://services.arcgis.com/P3ePLMYs2RVChkJx/arcgis/rest/services/USA_Major_Cities_/FeatureServer
Safe are aware of the issue, you can revert to 3.20.2 to avoid the issue.


