Your system information

• Steam client version (build number or date): 1591052255
• Distribution (e.g. Ubuntu): Manjaro Linux
• 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:

Trying to view game properties for a game using a deleted Steam Play compatibility tool causes the Steam client to crash.

Steps for reproducing this issue:

1. Download a custom Steam Play compatibility tool and install it to ~/.steam/root/compatibilitytools.d/ (ex: https://github.com/stevenlafl/Proton/releases/tag/proton-5.0-7-sdk148 fixes for Scrap Mechanic)
2. Restart Steam
3. Set a game to use the aforementioned compatibility tool
4. Remove the tool from ~/.steam/root/compatibilitytools.d/
5. Restart Steam
6. Right-click the game in your Steam library and select "Properties..."