Steam

Steam runs natively on Linux. You can probably just install it from your App store.

Usually you want to use Steam (Runtime). Only use Steam (native) if you know why you want to use it. If you use the Flatpak version, you will also need to use the Flatpak version of other software that you want to use with it, like MangoHud.

Enable Steam Play for all games

In order to run games that are not explicitly whitelisted by Valve, go to Steam -> Settings -> Steam Play and check "Enable Steam Play for all other titles" and then select "Proton Experimental" in the drop down menu.

It's usually a good idea to use Proton-GE instead of Proton Experimental. It has lots of benefits like improved game compatibility, raw mouse input, additional codecs for cutscenes, and much more. Installation instructions are here. If you want the latest features, you have to update it manually, though.

ProtonUp-Qt

You can use ProtonUp-Qt to make the installation and update process of Proton-GE simple:

• 1. Download the ProtonUp-Qt AppImage
• 2. Mark the AppImage as executable
• 3. Double-click the AppImage to run ProtonUp-Qt

Alternatively, you can install it from Flathub.

Launch Options

You may find something like -screen-width 1280 -screen-height 720 -screen-fullscreen 0 on protondb. These are launch options.

To use them, you right click on the game, and in the general tab, there is a field called launch options. You paste them (for example %command% -screen-height 1920 -screen-width 1080 -screen-fullscreen) in there.

%command% is the command to start the game. Some launch options go before this command (commands to execute programs, for example gamemoderun or mangohud), and some go behind it (flags that are passed to the game itself, typically stuff that starts with a -).

Steam Tinker Launch

Steam Tinker Launch is a swiss army knife tool that allows easy customization of multiple options for Steam games.

It includes helpers for custom commands, Vortex, Mod Organizer 2, Proton GE, Proton/DXVK/wine options, winetricks, ReShade + easy selection for shaders, FSR, debugging, side-by-side VR automation, SteamGridDB, SpecialK, Proton KillSwitch, Gamescope, GameMode, and more. You can find a more comprehensive list of features in the wiki (dropdownlist on the right).

File Locations

Steam Folder

If you use the Steam Flatpak, your Steam folder is ~/.var/app/com.valvesoftware.Steam/data/Steam/

If you use the "normal" package, your Steam folder is in~/.local/share/Steam/

Games and Save Files

Your games are in <steam_folder>/steamapps/common/<game_name>.

Your save games are in <steam_folder>/steamapps/compatdata/<some_number>/pfx/drive_c/<windows_path>. In order to know which number is correct, you can just use the search functionality of your file manager (probably ctrl + f) to search for the game name, or type find <steam_folder>/Steam/steamapps/compatdata/ | grep -i "<game_name>" in the terminal.

You have to substitute <steam_folder> and <game_name> with the actual thing, of course.