Overview
JEP-200 has been integrated into Jenkins weekly builds
and (if all goes well) will be a part of the next LTS line.
In a nutshell, this change is a security hardening measure
to be less permissive about deserializing Java classes defined in the Java Platform or libraries bundled with Jenkins.
For several years now, Jenkins has specifically blacklisted certain classes and packages according to known or suspected exploits;
now...