It's always been a rule in TRIM that you can't edit e-mail messages, hence can't make new revisions. I guess if that user really wants to, they could drag & drop the e-mails into TRIM as MSG files from their desktop. This way TRIM should allow them to drag & drop a later message from the thread onto the same record and make a new revision.
Note: Any posts I make on this forum are my own personal opinion and (unless explicitly stated) do not constitute a formal commitment on behalf of HPE.
(Please state the version of CM you're using in all posts.
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