Proton Launch Script

ProtonLaunch.sh

#!/bin/sh

# Application path
APP_PATH="$(dirname "${BASH_SOURCE[0]}")"
cd "$APP_PATH"

# Executable file
APP_EXEC="$APP_PATH/.exe"

# Steam / IDs
export SteamAppId=""
export SteamGameId=""

# Steam / Client path
export STEAM_COMPAT_CLIENT_INSTALL_PATH="$HOME/.steam/steam"

# Steam / Apps path
STEAM_APPS_PATH="$STEAM_COMPAT_CLIENT_INSTALL_PATH/steamapps"

# Steam / Compat data path
export STEAM_COMPAT_DATA_PATH="$STEAM_APPS_PATH/compatdata/$SteamAppId"

# Proton / Path
PROTON_PATH="$STEAM_APPS_PATH/common/Proton 4.11"

# Proton / Executable script
PROTON_EXEC="$PROTON_PATH/proton"

python "$PROTON_EXEC" run "$APP_EXEC"

This script is nice, but it doesn't work if you are attempting to launch a game stored on a Steam library folder outside of the home directory default library.
It also does not use best practices with regards to variable expansion.

To deal with this, I took the liberty of forking the script. For anyone interested in launching games on external Steam libraries (or just a more robust script in general), check it out here:

https://gist.github.com/lunalucadou/132a84d6e5d248847f9e90160f7789d7