please ignore initial repro project and use TestReadback.zip attached later
*somewhere deep inside LWRP we decide to use this format for metal - this does not make this issue metal specific

Steps to reproduce:
1. open TestReadback scene and press play

Actual Result:
there may/will be asserts and errors. The most important part is that script attached to camera shows texture copy of RT - they will be very different (to make sure script make sense you can tweak it to use "saner" format)

*please note that you can freely ignore ValidateFormat error if that happens - it is simply logged (not an exception) and it happens because c#-side SystemInfo.IsFormatSupported is very weird

THE reason:
on all platforms AsyncReadback reads data from texture as is and then use ImageReference to do on-CPU conversion. ImageReference works strictly with TextureFormat and not all GraphicsFormat/RenderTextureFormat can be mapped to TextureFormat

please note that repro uses GraphicsFormat.B10G11R11_UFloatPack32 but it will be reproduced with RenderTextureFormat.RGB111110Float

hence i removed regression flag but i keep "first affected version" as i didnt bother to check that way back