Tanel Kiis

I looked at it a bit more and the issue seems to be with the airflow.models.taskmap.TaskMap design. The airflow.models.taskinstance._record_task_map_for_downstreams method does not look at the multiple_outputs value and will create...

The same issue occurs when not using task groups, but it is handled a bit more gracefully: https://github.com/apache/airflow/blob/8914e49551d8ae5ece7418950b011c1f338b4634/airflow/models/mappedoperator.py#L120-L134

Did not change `SimpleOverlayArea`, will get to it after initial review. Perhaps this approach is not OK. `SimpleOverlayAreaTest` will fail until so.

I went ahead and fixed the `SimpleOverlayArea` also. The tests should now all pass

Pinging @dr-jts for a review on this.

I have never worked with kubernetes, but based on the triggering code: https://github.com/apache/airflow/blob/1f29d844411522e9a2cd4a14c3573e903b4e5074/airflow/www/views.py#L1786-L1794 I believe this diff could get you in the right direction. ```diff --git a/airflow/executors/kubernetes_executor.py b/airflow/executors/kubernetes_executor.py index bdac0889f..fe25d25e8...