Does Email to Case Premium Support Salesforce's Message-Id Threading?
Starting in Winter 21, Salesforce introduced a new enhancement for standard Email-to-Case where incoming emails are matched to existing cases based on the Message-Id found in email headers instead of the Thread Id included in the Subject/Body of the email. https://releasenotes.docs.salesforce.com/en-us/winter21/release-notes/rn_email_to_case.htm This change was made specifically for standard Email-to-Case, and doesn't directly impact the behavior of Email to Case Premium. That being said, we understood how this functionality could also be beneficial for Email to Case Premium customers, and as of version 8.49, it has been updated to work seamlessly with the new Message-Id Threading behavior introduced by Salesforce, as long as EmailMessage.MessageIdentifier is getting populated. For information about the new Lightning Threading Behavior introduced by Salesforce in Spring '23, please refer to this knowledge article https://kb.vicasso.com/?kb=000005319.