Successful re-run of previously 'broken' stage does not result in 'fixed' notification

[michaelbannister]

I have a pipeline/stage which occasionally fails in a non-deterministic way (e.g. due to environmental issues). When this fails, I correctly get a BROKEN notification to Slack. If I re-run the stage, and it passes, I'd expect to get a FIXED notification, but I don't.
On the next run of that pipeline/stage, it passes again, but again I don't get any notification. So in my Slack channel it appears that the build is still broken.

Looking at GoNotificationMessage_FixStageTest.java it seems like this is the second scenario:

My config contains:

  pipelines = [{
    name  = ".*"
    stage = ".*"
    group = "myapp-build"
    state = "broken|failed|fixed"
    channel = "#team-myapp"
  }

Am I right in thinking this should be working?
Any ideas to help me debug?

GoCD 17.11.0
gocd-slack-build-notifier 1.4.0-RC11