/usr/share/java/jenkins-htmlunit.jar is in libjenkins-htmlunit-java 2.6-jenkins-6-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/jenkins-htmlunit-2.6-jenkins-6.jar
/usr/share/java/jenkins-htmlunit-2.6-jenkins-6.jar