Original exception gets masked by later exception

When executing the tasks of a query and a failure happens in a task, the original exception can get masked by a later exception leading to the loss of the root cause of the query failure. As an example, when a task encounters a failure during opening its pipeline, the pipeline will be closed as usual (and the failure should be reported). However, if another failure happens during closing the pipeline, this later exception masks the original exception. There is no way to debug such cases any further since the root cause is gone.