protonscr

Use STEAM_COMPAT_CLIENT_INSTALL_PATH on linux inside steam.exe stub

protonopen Feature Request
ValveSoftware/Proton#9068 · opened 2025-09-25 by TukanDev · updated 2025-09-25 · 2 comments · github
TTukanDev 2025-09-25 github

Feature Request

I confirm:

  • [x] that I haven't found another request for this feature.
  • [x] that I have checked whether there are updates for my system available that
    contain this feature already.

Description

Currently it seems proton prefix's steam.exe stub does not utilize STEAM_COMPAT_CLIENT_INSTALL_PATH to load steamclient.so instead it uses hardcoded path to $HOME/.steam/sdk64/steamclient.so which is a symlink but that is less of importance here.
Problem arises when you want to use proton outside of steam completely and do not have that symlink $HOME/.steam path made all games will crash with attached image in the issue.
Since from my snooping around the code MacOS checks put in place utilize the env var just fine to open steamclient.dylib only linux uses hardcode path.

Justification [optional]

This issue is only related to proton itself as its the only set of runner having steam.exe stub

Risks [optional]

I guess people using proton and making custom launchers (like me for example) will be forced to set STEAM_COMPAT_CLIENT_INSTALL_PATH to real path with the steamclient.so file to fix the issue.

References [optional]

Could not find any

Crash image:
Image

Kkisak-valve maintainer 2025-09-25 github

Hello @TukanDev, so that it's clear, Proton is a compatibility tool explicitly created to support Steam. Using it outside of Steam is not supported making this request out of scope for the project.

Having written that, we'll see if a Proton dev has any interest in this request.

TTukanDev 2025-09-25 github

Hello @TukanDev, so that it's clear, Proton is a compatibility tool explicitly created to support Steam. Using it outside of Steam is not supported making this request out of scope for the project.

Having written that, we'll see if a Proton dev has any interest in this request.

Hello Kisak!
I am aware of this and I do not expect any special support it is just that i noticed that macos side does utilize env var properly but linux side completely ignores its existence which I found weird unless there is some specific reason why it is ignored.
I thought its better to report directly to upstream as all variation of proton like proton-ge for example pull from this repository.

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