When an email includes a Thread ID (Ref ID) in the body, the Email Feed Item Body is truncated at that point. The purpose of this design is to prevent duplicate content from appearing in the Case Feed: since the Thread ID marks the beginning of quoted text from a prior email in the thread, that prior email has most likely already been created as a separate Feed Item. To streamline the view and prevent duplication, Salesforce truncates the quoted content.
This is expected behavior and not a bug. If customers need to view the complete email body, they can open the original email from the Activity Timeline.
If an Email includes a Thread ID (Ref ID) in the body, then the Email Feed Item Body is truncated at that point. The purpose of this is that if a Thread ID is included in the body of the email, it is very likely that directly below it, is quoted text from a previous email in the thread. This email has most likely been created as an Item in the Case Feed. To streamline the view and prevent duplication, the quoted text from a previous email in the thread is truncated.
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