docs: def action_signal_triggered(self, model, prop_name, info):
          """When the action was performed, we have to set the dirty flag, as the changes are unsaved"""
          # print("ACTION_signal_triggered state machine: ", model, prop_name, info)
          self.state_machine.marked_dirty = True
          msg = info.arg
          if model is not self and msg.action.startswith('sm_notification_'):  # Signal was caused by the root state
              # Emit state_action_signal to inform observing controllers about changes made to the state within the
              # state machine
              # print("DONE1 S", self.state_machine.state_machine_id, msg, model)
              # -> removes mark of "sm_notification_"-prepend to mark root-state msg forwarded to state machine label
              msg = msg._replace(action=msg.action.replace('sm_notification_', '', 1))
              self.state_action_signal.emit(msg)
              # print("FINISH DONE1 S", self.state_machine.state_machine_id, msg)
          else:
              # print("DONE2 S", self.state_machine.state_machine_id, msg)
              pass