add: gtk_widget_show_all ( widget );
context: void gsb_assistant_add_page ( GtkWidget * assistant, GtkWidget * widget, gint position,			      gint prev, gint next, GCallback enter_callback ){    GtkWidget * notebook;    notebook = g_object_get_data ( assistant, "notebook" );    gtk_notebook_append_page ( notebook, widget, gtk_label_new("") );    g_object_set_data ( assistant, g_strdup_printf ( "prev%d", position ), prev );    g_object_set_data ( assistant, g_strdup_printf ( "next%d", position ), next );    g_object_set_data ( assistant, g_strdup_printf ( "enter%d", position ), enter_callback );}