It would depend on how the values are being added or removed from the field, i.e. one at a time with the document being saved each time in between or if the field changes are done in bulk.

The "Write Field Value" event will record the action each time the field is changed and document saved, and it will just show what values are currently in that field. From the screenshot in my previous post, a user added A, B, C, and D at the same time and then saved the document. Then a minute or so later, the user removed the values C and D and then saved the document again. That's why there's only two events.

See the screenshot below of what it would look like if the user added and removed the field values individually:

What does it look like in str_val field for you in database where prop_name is 'Multivalue' (fieldname)? Str_val doesn't show values separated by commas for me. Just one value at a time. I'm pulling by query. Where prop_name is fieldname and event_type is 28.