gtk:popover-default-widget (popover)

popover -- a gtk:popover widget
widget -- a default gtk:widget widget, or nil

The gtk:popover-default-widget function gets the widget that should be set as the default widget while the popover is shown. The (setf gtk:popover-default-widget) function sets the default widget.

The gtk:popover widget remembers the previous default widget and reestablishes it when the popover is dismissed.