Jan
I had the same problem and created a pull request to solve this: https://github.com/iammerrick/grunt-parallel/pull/45 for this.
Also interested in a feature which allows to handle network errors. In our tests we want to assert that a server is no longer reachable, so a network error is...
See also here: https://github.com/zammad/zammad/issues/4589 or here: https://stackoverflow.com/questions/75444763/python-imaplib-fetching-icloud-mail-rfc822-not-working