Steps to reproduce:

1. Add open xr or mock hmd xr provider which has foveated rendering support to your project.
2. in the player settings enable vulkan and xr settings enable foveated rendering for windows
3. Attach script to a GO or camera in scene[^FR.cs]
4. build and run
5. compare to DX12

Actual results: 

When using Vulkan there is no change in rendering between FR 1.0 and 0.0 as seen when running with DX12

Expected results: 

Edges of screen display in lower resolution

Reproducible with versions: 

2022.3?  I didn't got back to 22.3 to test this yet

but open xr only on 2023.3+

Not reproducible with versions: 

Can’t test with versions: 

2021.3

Tested on (OS): 

Windows
Notes:

• currently mock hmd does not have this support merged into trunk but you can use branch foveated-rendering/d3d-vulkan from [https://github.cds.internal.unity3d.com/unity/xr.sdk.mock-hmd]
• open xr support is in PR as well https://github.cds.internal.unity3d.com/unity/xr.sdk.openxr/pull/891