HDRP Custom Pass Volume display issue when running via Proton (Windows build)

I have a Unity 6 HDRP project with in world canvas GUI’s.

(Working example)

I use a custom pass volume to avoid the world canvas from receiving post processing effects ([White Balance], [Shadow, Midtones, Highlights], [Color Adjustments]), this works great for a Windows build running on Windows.

The issue is when I run the game via Proton (Steam Deck), the custom pass volume doesn’t display as expected - note how dark it is.

It displays fine when running with a native Linux build - I had to change the render texture videos to either transcode VP8 from within Unity, or convert the base video file to WebM VP8 encoded. However, this doesn’t appear to be a viable option as my local test builds have concluded SteamWorks.NET and Unity Input System 1.11.2 both have multiple critical issues/bugs running on native Linux builds.

Interestingly, I have some custom passes to display my player/guns above everything (prevent clipping) and this works fine across all builds.

A work around is to disable the custom pass when running via Proton on Linux, but this isn’t really ideal because then the canvas is receiving the post processing effects.

I have tried just about every configuration for the canvas custom pass, but the end result is always the same. I realise this is very likely an issue with Proton/Wine, but I was hoping someone else might have experienced the same and/or have a solution on the Unity side?

This issue has been consistent within my project across various Unity 2022, 2023 and now Unity 6 versions.

Hello,

I’ve tried looking if we had similar issues reported by other users or internally reported, but I couldn’t find anything. So I would like to ask you to report this issue via the Editor Bug Reporter and make sure to attach your project.

To do so, please do the following steps:

  1. Open the Project where you encounter this issue
  2. Reproduce the issue to make sure it’s still occurring
  3. Open the Bug Reporter via the toolbar ( Help → Report a Bug…)
  4. Fill out the information and make sure to link this Discussions thread URL in the description too

This would greatly help us out and speed up things in the testing/reproduction process of the issue.

So if you do decide to report it: Thank you in advance!