/indra/newview/skins/default/xui/en/panel_outbox_inventory.xml

<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
<outbox_inventory_panel
    name="inventory_outbox"
    start_folder="Outbox"
    follows="all" layout="topleft"
    top="0" left="0" height="165" width="308"
    top_pad="0"
    bg_opaque_color="DkGray2"
    bg_alpha_color="DkGray2"
    background_visible="true"
    border="false"
    bevel_style="none"
    show_item_link_overlays="true"
    tool_tip="Drag and drop items here to prepare them for sale on your storefront"
    >
    <scroll reserve_scroll_corner="false" />
</outbox_inventory_panel>