Onedaywhen's answer to Lawlera's query about restricting changes to the Username box under Options was:

"That's why you should always check the username (or full name) they
used to log on."

I am trying to prevent impersonation in a shared workbook with tracked changes. What does the above reply mean (How to check? How can it be recorded?) and how could I use it to stop abuse of the Username box?

Reply in very straightforward layman's terms would be very much appreciated. Thanks.