Even though FINAL FANTASY VII REBIRTH is rated as Steam Deck Verified, it did launch with some problems on Linux / Steam Deck but Valve's Proton developers are moving quickly to improve it.
VKD3D-Proton, the layer that translates Direct3D 12 to Vulkan, had some updates to work around some issues that have been seen. Developer Hans-Kristian Arntzen said "For AMD hangs, we have two game workarounds merged now which have successfully worked around some hangs on our end at least" and those are:
Both of those have been merged into VKD3D-Proton, and a new Proton Hotfix update has been made available, which Valve have now set as the default for FINAL FANTASY VII REBIRTH. So if you have set a specific Proton version on it, you should unselect it to get it to use the latest Proton Hotfix and get a more stable experience right now.
Confused on all the Proton versions? Check out my guide to explain more.
At least for AMD GPU users it will be better now but we're still waiting for NVIDIA driver updates to improve the situation there on Desktop Linux.
The latest 570 driver does not include the mesh shader fix required.
Looks like we may be waiting for the next release (hopefully)
550.40.83
Fix gl_NumWorkGroups behavior for mesh shaders
https://developer.nvidia.com/vulkan-driver
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