Thank you for reporting the problem. We will fix it in the very next maintenance version of the Release 6.5, it will be 6.5.6 I believe.
At the moment you can use the following workaround:
Create CustomAppUI class:
public class CustomAppUI extends AppUI {
protected void setupUI() throws LoginException {
if (!app.getConnection().isConnected()) {
if (!((CustomApp) app).loginOnStart()) {
app.getConnection().loginAnonymous(app.getLocale());
}
} else {
app.createTopLevelWindow(this);
}
}
}