I was looking through Youtrack and decided on a whim so look for the oldest issues :)
What is most interesting is that although some of these are created 10 years ago :O they still have recent comments!
https://youtrack.jetbrains.com/issue/IDEA-28657 (NB: I don't care about this issue - just giving an example)
I think all companies should hire a Zombie Killer to go through backlogs! :)