Thanks @skyehansen. Your suggestion to add the "additional info" fields helped. I'll summarise here because it might be helpful to other users.  "Additional Info 1" seems to contain the event handler that generated the "digest", which I assume are either e-mails sent OR notifications shown on platfo...

Dear all.  Most of the change types present in the Journal Entry reports are easy to understand (such as "add" or "edit"), however I must confess it's not clear to me how to interpret the change type "Digest". I've heard it would be related to comments, but could not verify this in the Workfront doc...