I know there are hundreds of questions on "How to kill a defunct process" but in all of those I found the final answer was: "Don't worry. They don't use any resources." and that basically you either have to kill the parent or reboot the system.
In my case I can neither reboot the system, nor kill the parent (gnome-shell) process.
While my zombie does not eat CPU or RAM, it prevents me from using audacity. The defunct process was audacity and whenever I try to launch it now it reports that it's already running, even though it has been -9 killed (after it became unresponsive).
What are my options? Can I "rename" the process somehow or assign another PID to it?
gnome-shellis actually the parent of the Audacity process? Did you check withpstree? – Kusalananda Aug 04 '18 at 08:01ps -efandgnome-system-monitor. – confetti Aug 04 '18 at 22:30