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Trying to modify Unreal Engine for the recent EDR support on iOS, and I can't get it working properly. Extended colors are getting clipped. wantsExtendedDynamicRangeContent is enabled on the layer. I tried both MTLPixelFormatBGR10A2Unorm/kCGColorSpaceITUR_2100_PQ and MTLPixelFormatBGRA16Float/kCGColorSpaceExtendedLinearSRGB with the appropriate color transformations in shader code, and the SDR-range colors look fine, but the extended colors do not. Metal frame debugger shows the pixel values are what I want them to be. I'm testing this with iPad Pro 5 in Reference Mode. I don't set edrMetadata because I don't want the device to do any tonemapping. Is there something else I need to set? IPad Pro 5 and iPhone XR report 16/2 for potentialHDRHeadroom (good), but currentHDRHeadroom is always 1 (bad) unless I put the iPad Pro 5 in Reference Mode, where it becomes 10 as expected. I played an HDR video recording of our PC build on the device, so I know the device is capable of rendering HDR correctly... Can I get some help please? Is there an iOS EDR sample published that I can use for reference maybe? :D