You can see multiple entries for `_class` for the entries in `PipelineStep.actions`
Invalid JSON is produced during remote api operations when a changeSet contains duplicate keys.
Attached JSON instead of inline because JIRA is special.
Seems to have come up in the past, so I guess this is a regression: https://issues.jenkins-ci.org/browse/JENKINS-13336
Super stale, and no longer an issue?