We're using a Global Action "Create Case" displayed through a Customer Portal for authenticated users. Since it's a Global Action, we cannot predefine the AccountID with the authenticated user's UserId.ContactId.AccountID.
We would like to use Validation Rules to check if the User's Account record values meets the eligibility criteria for case submission.
Writing a Validation Rule on ISNEW() and AccountId.CustomField__c throws an error every time since the AccountID is null at the time of submission, but the field IS populated by some standard config by the time it saves it as a record in Salesforce.
What standard component of Salesforce is setting the AccountID (Account Name) field on the Case record itself?
You might have to use custom lightning component or lwc to meet this requirement
