"widgets/modest-window-mgr.c" @299

        if (priv->queue_change_handler > 0) {
                g_signal_handler_disconnect (G_OBJECT (modest_runtime_get_mail_operation_queue ()),
                                             priv->queue_change_handler);
                priv->queue_change_handler = 0;
        }

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"widgets/modest-folder-window.c" @284

        if (g_signal_handler_is_connected (G_OBJECT (modest_runtime_get_mail_operation_queue ()),
                                           priv->queue_change_handler))
                g_signal_handler_disconnect (G_OBJECT (modest_runtime_get_mail_operation_queue ()),
                                             priv->queue_change_handler);