docs: private void requestProcessed(FacesContext facesContext)
      {
          if(!_firstRequestProcessed)
          {
              // The order here is important. First it is necessary to put
              // the value on application map before change the value here.
              // If multiple threads reach this point concurrently, the
              // variable will be written on the application map at the same
              // time but always with the same value.
              facesContext.getExternalContext().getApplicationMap()
                  .put(FIRST_REQUEST_PROCESSED_PARAM, Boolean.TRUE);
              
              _firstRequestProcessed = true;
          }        
      }