On Manage Jenkins page, I see the following warning message:
Warnings have been published for the following currently installed components.
however my environment injector plugin is already 2.1.6.
Also in Jenkins log, there is a warning:
WARNING: Attempt to (de-)serialize anonymous class hudson.FilePath$27 in file:/var/cache/jenkins/war/WEB-INF/lib/jenkins-core-2.121.2.jar; see: https://jenkins.io/redirect/serialization-of-anonymous-classes/
Anyway to get rid of this?