The steps for "validating GPURenderPipelineDescriptor" appear to be incorrect.

Specifically the wording:

descriptor.fragment.targets[0].format must be a GPUTextureFormat with an alpha channel.

but using alphaToCoverage requires blending at least on Metal.

Is it intentional that it says 'an alpha channel' and not 'supports blending'? We notice a validation issue when rgba8-sint is used with alpha to coverage, as MTLPixelFormatRGBA8Sint does not support blending.