You can take advantage of the rollback functionality to keep the Activity Window clean. Find a step-by-step example below:
1. Here you see a screenshot of two activity windows showing two perspectives of the same situation: the upper windows shows failed tasks only; the lower one shows the whole structure
2. In the next step you open the monitor of the parent of one of the failed tasks and choose 'rollback to this task' on the failed task
3. After the successfull rollback choose 'rerun' from within the 'Modify Workflow' conect menu on workflow level
4. As you can see on the next screenshot, the failed instance (RunID: 1110343) vanished from the upper activity window. The final status of this task (ENDED_ROLLBACK_EMPTY) is shown in the lower activity window
In case you have rollback enabled on the particular task the status after a successful rollback will be ENDED_ROLLBACKED. If the rollback fails the task will get the status FAULT_CUSTOM_ROLLBACK.