Hello @actionschnitzel, we're using one issue report per unofficially supported game title, so I've gone ahead and transferred this issue report to https://github.com/ValveSoftware/Proton/issues/8315#issuecomment-6398557477.
PROTON_LOG=1x1 2026-10proximagameanticheatshell.dllx1 2026-10
Compatibility Report
steam-1273560.log
System Information
I confirm:
Symptoms
When launching DeathSprint 66 on Linux via Steam, a Wine C++ Runtime Library assertion dialog appears:
C:\windows\system32\rundll32.exe../src-wine/dlls/wineopenxr/openxr_loader.c651!_status && "CreateInstance"The game does not proceed normally until the assertion dialog is dismissed by clicking OK. After closing the dialog, the game continues starting and appears to run.
This issue started occurring on October 25, 2026. The game previously launched without this dialog.
The Proton log shows that
DeathSprint66.exeandProximaGameAntiCheatShell.dllare loaded. It also contains COM-related errors shortly before the process continues.The issue appears to be related to Wine/Proton's OpenXR initialization, but the exact cause is currently unknown.
Reproduction
wineopenxr/openxr_loader.c, line 651.The issue has so far been observed consistently during startup.
Additional information
The following launch option was used to generate a Proton log:
Relevant log excerpt:
Full Proton log:
steam-1273560.log(to be attached).System information and the exact Proton version will be added once collected.