/usr/share/java/stapler-adjunct-timeline.jar is in libstapler-adjunct-timeline-java 1.3+dfsg-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/../maven-repo/org/kohsuke/stapler/stapler-adjunct-timeline/1.3/stapler-adjunct-timeline-1.3.jar