radeonsi: steam (steamwebhelper) fails to launch after update to 24.2.0-rc1

System information

• OS: Exherbo Linux
• GPU: 2f:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 32 [Radeon RX 7700 XT / 7800 XT] [1002:747e] (rev c8)
• Kernel version: Linux exherbo 6.10.0 #1 SMP PREEMPT_DYNAMIC Mon Jul 15 20:03:48 CEST 2024 x86_64 GNU/Linux
• Mesa version: OpenGL version string: 4.6 (Compatibility Profile) Mesa 24.2.0-rc1
• Xserver version: - (Wayland)
• Desktop manager and compositor: KDE Plasma / KWin

If applicable

• DXVK version: -
• Wine/Proton version: -

Describe the issue

After updating to 24.2.0-rc1 steam fails to launch, a downgrade back to mesa 24.1.4 makes it start/work again.

Regression

It worked with 24.1.4 and after downgrading back to 24.1.4 it works fine but not with 24.2.0-rc1.

Log files as attachment

Probably relevant part:

src/steamUI/steamuisharedjscontroller.cpp (619) : Failed creating offscreen shared JS context
src/steamUI/steamuisharedjscontroller.cpp (619) : Failed creating offscreen shared JS context

Complete log: steam.log

Screenshots/video files (if applicable)

Any extra information would be greatly appreciated

For testing purpose to see if it might be related I've applied !30257 (fb66f9fb) to get rid of the MESA-LOADER: failed to open radeonsi: driver not built!) message but it didn't change anything.