I’ve just pushed beta 1734683, containing a partial fix for the zombie process issue.
The underlying issue is that there is a background thread that can fail to initialize properly, and if it does fail to initialize it blocks termination of the entire process. That will need to be fixed by the launcher team, and affects all platforms.
However, the elg warning people were seeing was a symptom of a problem which was causing that thread to fail to initialize 100% of the time, and I have fixed that issue. You’ll get one last zombie process when the update to 1734683 happens, as the version it’s upgrading from fails to close properly. After that, for most people the zombie process issue should go away.