"Closing Group Chat Room error" when exit Spark

morning everyone. i'm using Spark 2.6.3

if i leave any group chat room opened and select Spark menu Exit, client log will show:

SEVERE: Closing Group Chat Room error.

java.lang.IllegalStateException: Not connected to server.

 

i wonder if it is useful to change the order of following code in org.jivesoftware.MainWindow:

from:

    publicvoid shutdown() {        final XMPPConnection con = SparkManager.getConnection();          if (con.isConnected()) {            // Send disconnect.            con.disconnect();        }          // Notify all MainWindowListeners        try{            fireWindowShutdown();        }        catch (Exception ex) {            Log.error(ex);        }        // Close application.        if(!Default.getBoolean("DISABLE_EXIT"))            System.exit(1);      } 

to:

    publicvoid shutdown() {        final XMPPConnection con = SparkManager.getConnection();          // Notify all MainWindowListeners        try{            fireWindowShutdown();        }        catch (Exception ex) {            Log.error(ex);        }          if (con.isConnected()) {            // Send disconnect.            con.disconnect();        }          // Close application.        if(!Default.getBoolean("DISABLE_EXIT"))            System.exit(1);      }