Compatibility Report

• Name of the game with compatibility issues: Borderlands 2
• Steam AppID of the game: 49520

System Information

• GPU: AMD Radeon RX 9070 XT
• Video driver version: Mesa 25.3.1
• Kernel version: 6.17.7-ba22.fc43.x86_64 (64-bit)
• Link to full system information report as Gist: https://gist.github.com/Candunc/ff42f3e8cd42024d9a7d685a66455e7d
• Proton version: Proton Experimental, Proton Hotfix, Proton 9.0, Proton 10.0

I confirm:

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

Symptoms

Borderlands 2 no longer launches with Vulkan backend. Unclear if this is a regression in Bazzite/Mesa drivers or in the Proton vulkan libraries. This was working just a few weeks ago, so there is a regression somewhere.

Adding PROTON_USE_WINED3D=1 %command% to the launch options allows Borderlands 2 to launch, though with a heavy performance penalty.

10509.888:0280:0284:err:msvcrt:_wassert (L"!status",L"../src-wine/dlls/winevulkan/loader.c",392)
steam-49520.log

Reproduction

Launch Borderlands 2 using Proton compatibility layer (Not native Linux runtime). I've tried Proton Experimental, Proton Hotfix, Proton 9.0 and Proton 10.0 with no noticeable changes. Note that launcher starts as expected. Press 'Play' and note that it appears that no executable launches.

In the Steam launch options, add PROTON_USE_WINED3D=1 %command%. Re-launch the game and press play in the launcher, and note that the game launches correctly.