• Install Squad on a Linux machine / Steam Deck
  
• Go into the game Properties. In the Compatability tab select either Proton Hotfix for the latest version from Steam or install GE-Proton Latest for the auto-updating version of Glorious Eggrolls version of Proton.
  
• Search your Steam library for EasyAnti Cheat and install that in the main Steam location (The default default location)
  
• Profit

Tried without any additional shims, game works fine.

A wonderful aspect of WINE and Proton and Linux is the open-source nature of these things means the community can find and fix bugs when the developer themselves is snowed under. You may find the additional steps in this guide are no longer required.

1. Install/Verify Squad
   
2. Tell Squad to use the most recent Proton version you have
   
3. Launch Squad

If the game runs fine and you can play a server without getting kicked out, maybe you only want to look at enabling feral's gamemode and using Glorious Eggroll Proton.

It's based on the WINE shim, Proton is developed by Valve. There are other variants but for now the Glorious Eggroll[github.com] version of Proton is the de-facto community favourite due to the way it integrates proprietary and alternative drivers to do things like video playback in certain formats.

For the purposes of this guide I recommend ProtonPlus[flathub.org]. Get the most recent GE version then restart Steam.

Then click the "cog"/settings icon, select the Compatability tab, drop down the list and select the GE version you just installed.

Running any Linux version of Steam, simply search the Steam library for "proton". It will list all versions, you always have all versions, you don't need to install every version. Sometimes ProtonDB will suggest an older version, sometimes you can get away with a recent ProtonGE.

But developers are really lazy apparently! All they need to do is turn it on in their dev environment according to Epic[dev.epicgames.com].

Following the guide on https://squadfm.org/#installation-linux-only we carry out the following steps

1. Get the EAC files from Valve's official Github[github.com] >here<[github.com].
   
2. Using the "cog" or right-click on Squad and select Manage Files, in your file browser navigate up until you see "\compatadata", enter that folder and look for "\393380"
   
3. Drill down into the directories "...\steamapps/compatdata/393380/pfx/drive_c/users/steamuser/Application Data/EasyAntiCheat/55/"
   
4. Copy the files from the downloaded .zip into that directory
   
5. Set "\55" to read-only
   
6. Set "...\steamapps/compatdata/393380/pfx/drive_c/users/steamuser/Temp/" to read-only
   
7. Tell Squad to use the most recent GE Proton and have a go

• Pictoral guide (WIP)
  
• Everlasting guide (WIP)

Anything you suggest, I'll add if I can prove it!