I have a declarative pipeline job. The Jenkinsfile has the following snippet:

post {
  failure {
    step([$class: 'Mailer', recipients: 'ci@example.com', sendToIndividuals: true])
  }
}

When the build fails, the addresses in the recipients string successfully receive mail. However the culprits responsible for the broken commit do not receive an individual email. As I have set the sendToIndividuals, I expect that they would. I've been unable to find any logs that might suggest a misconfiguration.

I have been able to workaround this issue with the mail-ext plugin by changing the above snippet to:

post {
  failure {
    step([
      $class: 'Mailer',
      recipients: ['ci@example.com', emailextrecipients([[$class: 'CulpritsRecipientProvider'], [$class: 'RequesterRecipientProvider']])].join(' ')
    ])
  }
}

But I had hoped that this would work without introducing another plugin.