winedevice.exe memory leak

I am running Ubuntu 20.04 on a rig with 32 GB of RAM. While playing Subnautica tonight, I started encountering significant stuttering, followed by a complete lockup of the system at the keyboard. I ssh'ed into the system (which took at least 5-10 minutes to get from a password prompt to a shell prompt), and on running top found winedevice.exe to be using ~85% of RAM, with total system swap usage around 32 GB. Typical total memory usage on the system tends to run 10-20 GB depending on what I have running, so I estimate that winedevice was eating up 40-50 GB. I killed winedevice.exe and Subnautica, but winedevice basically pushed everything else out to swap, so my ability to interact with the system is minimal while everything gets pulled back in. I'm posting from a separate device and will post Proton version info, etc, once the system is usable again.

Start by reviewing the reported Ubuntu 20.04 environment and the winedevice.exe memory-growth symptoms. Reproduce the Subnautica session while monitoring memory and swap, but first obtain the missing Proton version and confirm the game configuration. Done means identifying and fixing the leak with a regression check; the issue names no source file or test.