doom.sh

#!/bin/sh
LIB="~/.local/share/Steam/steamapps/common"
BINARY="$LIB/Proton 5.0/dist/bin/wine"
EXE="$LIB/DOOMEternal/DOOMEternalx64vk.exe"
ARGS="+in_terminal 1 +com_skipIntroVideo 1 +com_skipKeyPressOnLoadScreens 1 +com_skipSignInManager 1"
WINEPREFIX="$LIB/DOOMEternal/prefix" "$BINARY" "$EXE" $ARGS

I get the same thing when using the script about 'Unable to initialize Steam API' I wonder how @annmuor is not getting this?
I'm running Vulkan loaders 1.2.135.r2 on Manjaro with the Proton he provided.

I keep running into the same bash error, even when I have $LIB pointed right at the exact filesystem location where Steam is. I have Steam installed through Flatpak, if that makes any difference (so instead of /.local/share/ or /media/, Steam and my games are all under /.var/app/com.valvesoftware.Steam/).

@grand248 replace binary with drm-free one for sure :)

u/Kron4ek has a working version and has modified Proton on his GitHub so that you can run it. You still need the latest Vulkan headers and loader, as well as a special patch iirc, and of course the drm-free binary. I personally haven't gotten it working, but he's demonstrated that it will run and that its performance is very very shitty compared to running on Windows, which isn't surprising.