Earlier quoted context omitted.
Because it has to be reproducible. Help make it reproducible and show that to the developers.
We don't know how to make it reproducible. What developers should do on such a critical and long standing issue is to offer an extension that victims can install to volunteer to track the bug. So they can click a button when things are fine to take a snapshot, and click another one when they encounter it. I would install that and be part of the solution.
I've encountered several impossible to reproduced bugs in the past. And what I (or my team) would then do, is re-architecture (refactor) some pieces of software so that we could reproduce it. Like e.g. better logging, specialized layers/adapters/services, simpler logic, and -above all- better testability.