We have one or two jobs using the "Build when certain files are found" build trigger. One of those "certain files" is in a subdirectory of the JENKINS_HOME directory. Currently, it appears that I am not able to use the ${JENKINS_HOME} environment var in the directory field of the build trigger. It throws an error of "Directory not found"

Changing it to a hard-coded path (/var/lib/jenkins for example) works successfully.