Good point. If it was the only evidence and didn’t connect with anything else it would not be substantial proof. I would think it could add to a story but not be definitive proof? You are describing the defense against the screenshot which could be backed up by “expert” testimony. Here is something I found on e-mails being edited in outlook even: https://community.spiceworks.com/topic/1135234-can-i-protect... (questionable source)