file-menu:open-on-demand in frame:open-here-mixin

The menu item's on-demand method calls this method

• (send a-frame:open-here-mixin file-menu:open-on-demand item) -> void
     item : (is-a?/c menu-item%)

  Defaultly is this: (lambda (menu-item) (void))

  Sets the label of item to "Open Here..." if the preference 'framework:open-here? is set.