Vulkan Proton crash on Linux

I have the same error when starting the game with Vulkan selected, but when trying to change to Vulkan in game i consistently get the error on the first try and can then change successfully on the second try.
Just have to edit the production_Config.ini and do this again every time i start the game...

Tired of the actually not so occasional DirectX12 related freezes and the waiting for a fix that will probably never come, I looked for a satisfying workaround...

=> installed Steam via flatpak (newer mesa driver than debian stable one)

and it now launches with Vulkan !!!-D

(took me the whole day though, since I haven't read this at first :
"To add a game library on another drive, first you need to grant the app access to it: flatpak override --user --filesystem=/path/to/your/Steam/Library com.valvesoftware.Steam "

Hope this can help...