Problem with implicit Message Component in WD for ABAP

Hi,

I do some input checks in the method WDDOBEFOREACTION in my view controller. If there is sth. wrong, I use

DATA: 
  l_current_controller TYPE REF TO if_wd_controller,
  l_message_manager    TYPE REF TO if_wd_message_manager.

  l_current_controller ?= wd_this->wd_get_api( ).

  CALL METHOD l_current_controller->get_message_manager
    RECEIVING
      message_manager = l_message_manager.

  l_message_manager->report_error_message...

To add a message to the message manager. The message is displayed. If I add more than one message, then one is displayed and pushing the button "Show List" has no effect 😔

When I put the same coding on the Action Handler Method for my button, then pushing "Show List", shows the message list.

I thought WDDOBEFOREACTION is the correct method to do input check, so why does the message framework does not work correctly? Or ist this a bug?

Thanks a lot,

Sascha