I'm working on an Opportunity trigger and trying to pull the ID of a Contact that's connected via a lookup field on the Opportunity object called "Inbound_Contact__c". However, when this gets triggered on an Opportunity that has this lookup field filled out, the following line still outputs "NULL":
System.debug(opp.Inbound_Contact__r.Id);
Am I missing something on how to access the Id of this Contact? Thanks!