Rust Staging (700580) - "Steam Auth Failed"

Compatibility Report

• Name of the game with compatibility issues: Rust - Staging Branch
• Steam AppID of the game: 700580

System Information

• GPU: GTX 1080 ti
• Driver/LLVM version: 418.52.20
• Kernel version: 4.19.69-1-lts
• Link to full system information report as Gist: https://gist.github.com/Lyle-Tafoya/f58b9fb0c0f6d8c12e81bf96f4b5fc6c
• Proton version: 4.11-3, 4.2-9, 3.16-9

I confirm:

• that I haven't found an existing compatibility report for this game.
• that I have checked whether there are updates for my system available.

steam-700580.log

Symptoms

The client is unable to authenticate. As a result, it is not possible to join any Rust Staging Branch servers. However, this same issue does not occur when launching Windows Steam from Lutris using vanilla Wine 4.14. Using Wine 4.14 to launch the Windows version of Steam, I can successfully join Rust Staging servers. It's also worth noting that this issue is only present for Rust Staging servers and not normal Rust servers. However, this may change in the near future (as early as 09/05) as many features from Staging make their way into the main branch.

When testing with Proton 3.7, I encountered a different (but possibly related) issue immediately upon launching Rust Staging: "Steam Load Error - Is Steam Open? Please exit and try again with Steam open."

Reproduction

1. Launch "Rust - Staging Branch"
2. Hit F1 to bring up the in-game terminal
3. Enter the command "connect 50.35.92.184:28015". This will attempt to connect you to the only "Rust - Staging Branch" server which is set "server.eac 0", "server.secure 0", "server.encryption 0" (this is required). I am the one hosting it, but I can't say for certain how much longer I will continue. You can also host your own server, but it has to have the configuration mentioned above and must be a staging branch server to work.

At this point, you should be looking at the error "Steam Auth Failed".

Reproduce the report by launching Rust - Staging Branch, opening the F1 terminal, and running the provided connect command. Start by inspecting the attached steam-700580.log and compare behavior across the listed Proton versions; done means Steam authentication succeeds and the staging server can be joined.