Gtk.ImageMenuItem.prototype.set_accel_group

function set_accel_group(accel_group:Gtk.AccelGroup):void {
    // Gjs wrapper for gtk_image_menu_item_set_accel_group()
}

Specifies an accel_group to add the menu items accelerator to (this only applies to stock items so a stock item must already be set, make sure to call Gtk.set_use_stock and Gtk.set_label with a valid stock item first).

If you want this menu item to have changeable accelerators then you shouldnt need this (see Gtk.new_from_stock).

Since 2.16