Oddly enough, looking through the different files and I see a memorial_clipboard file in the assets\ui_screens\ui_personnel folder. I just don't see anything that references it. It looks like the personnelview.lua would have something to do with it. I did find this under assets\strings:
<Row ss:AutoFitHeight="0">
<Cell><Data ss:Type="String">PersonnelView.MemorialWall</Data><NamedCell
ss:Name="_FilterDatabase"/></Cell>
<Cell><Data ss:Type="String">Casualty<br/>List</Data><NamedCell
ss:Name="_FilterDatabase"/></Cell>
</Row>