⚠️ We're preparing some changes in order to support cross-platform cloud saves between Windows, Linux, and Steam Deck for X4: Foundations.
Please read our announcement: https://store.steampowered.com/news/app/392160/view/526493916198863080
@fell @egosoft You should, just in case.
You're right, there are currently two different save locations depending on the client you use on Linux. One location for the native Linux client, and one for if you run the game through Proton(like SteamOS does by default but is also an option for any other Steam on Linux user).
Once the update hits, X4 will no longer have two locations for saves. The native Linux location is going away and only the second type will persist.
Obviously this has no impact on Windows users as they would never have the option to play the native Linux version of the game.