Hello @jebez1, please add PROTON_LOG=1 %command% to the game's launch options and attach the generated $HOME/steam-$APPID.log to this issue report as a file. (Proton logs compress well if needed.)
Well I use Heroic Games Launcher now https://www.reddit.com/r/linux_gaming/comments/1jd90ph/how_to_download_epicinstallermsi_on_linux/
I was not able to reproduce. Following his instructions installed Epic Games Launcher fine for me.
PROTON_LOG=1x1 2025-03
Compatibility Report
System Information
I confirm:
EpicInstaller-18.1.3.msi steam-14400373260111839232.log
EpicGamesLauncher.exe steam-15982687951247114240.log
Symptoms
On Arch Linux KDE.
Add a Game
Add a Non-Steam Game...
EpicInstaller-18.1.3.msi
PLAY
Add a Game
Add a Non-Steam Game...
pfx/drive_c/Program Files (x86)/Epic Games/Launcher/Portal/Binaries/Win32/EpicGamesLauncher.exe
PLAY
A small window appears with a loading bar, VERIFYING UPDATE , INSTALLING PREREQUISITES then it close.
It worked before for a previous version of EpicInstaller-*.msi , I remember not the version.
It works on Windows 11.
Unlike on Windows 11, there is not the folder
pfx/drive_c/Program Files (x86)/Epic Games/Launcher/Portal/Binaries/Win64
although there is before, but both
pfx/drive_c/users/steamuser/Desktop/Epic Games Launcher.lnk
C:\Users\Public\Desktop\Epic Games Launcher.lnk
target Win32/EpicGamesLauncher.exe .
Hence I can't play Rocket League anymore on Arch Linux KDE, although it was on Steam...
Reproduction
See above.