This is the initial width for the instance list (in pixels) for VLF-ONE business objects.
It is used only the first time the user ever opens the business object. Thereafter the sizing that the user adjusted the panel to is always remembered (even between sessions) so this property is not used, unless the user clears the browser cache and restarts.
If a filter is displayed at the TOP or BOTTOM of the instance list, and the filter's designed width is greater than the instance list initial width, then the filter's width will be used to size the initial panel width.
This property is in the Business Object Instance List tab.