See JENKINS-66023 and https://github.com/jenkinsci/support-core-plugin/pull/298/files#diff-5a8ed81f72c628f3870f2fc2f9a0946cd6356e25cc62a71dde4e4f58be8a6607R170

2021-08-24 12:32:01.831+0000 [id=84]	WARNING	c.c.j.s.filter.ContentMappings#getAdditionalStopWords: Could not load user provided stop words as /var/jenkins_home/support/additional-stop-words.txt does not exist or is not readable.

This popped up in a paranoid self-testing pipeline after building and starting a Jenkins Docker image and then checking all logs for very defensively: any unexpected warning logs fail the self-test pipeline.

I think this new "additional-stop-words.txt" file must not exist and so it should not log a warning?