numeric
Whether or not the panel is in "multiple" mode. Only panels of type label, button, text and list can have such a mode. For other panels this element is invalid.
For labels and buttons in multiple mode, one of a choice of multiple images can be displayed. For a text panel in multiple mode, its text value can comprise multiple lines. For a list panel in multiple mode, multiple options may be selected.
It is a read-only element and cannot be changed after panel creation.