3810176 - SmartEdit Login Error: "Can't Get Access Token", Username Missing and PrincipalUid Null After Refresh the Login Page

1. After upgrading the Commerce version, SmartEdit login shows: "An error has occurred: can't get access token. Please contact your administrator."
   
   
   
2. Then refresh the page, SmartEdit loads only partially and the username is not displayed in the top-right user menu. SmartEdit webservice calls fail with error: {"errors":[{"message":"principalUid parameter cannot be null","type":"IllegalArgumentError"}]}.
   

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SAP Commerce Cloud

SmartEdit, access token error, can’t get access token, principalUid parameter cannot be null, permissionswebservices, OAuth JDK21, Spring Security 6, parseAccessToken, authentication.service.ts, username missing, authorization code, redirect URI, security-context-explicit-save, user principal null, webservices failure , KBA , CEC-SCC-COM-SEDIT , SmartEdit , Problem