Your system information

• Steam client version (build number or date): Feb 11 2020, at 19:27:00
• Distribution (e.g. Ubuntu): Pop!_OS 19.10
• Opted into Steam client beta?: [Yes/No] No
• Have you checked for system updates?: [Yes/No] Yes

Please describe your issue in as much detail as possible:

Describe what you expected should happen and what did happen. Please link any large code pastes as a Github Gist

I tried to play No Man's Sky using the Steam Linux Runtime as the compatibility tool.
expected: Play the game
happens: The Steam client erased all game's local files.

P.S. I had the same issue in another game (SCUM).

Steps for reproducing this issue:

1. On Linux download No Man's Sky game;
2. Force Steam Linux Runtime as the compatibility tool;
3. Try to start the game.