When trying to produce lossless JXL images, currently XYB encoded images are generated, and they are not technically lossless. libjxl will generate an error in this case in upcoming builds, see libjxl/libjxl#1270

As I understand basic_info.uses_original_profile should be true if the file is lossless to avoid XYB encoding, and false otherwise for better compression. I can see "jxl->info.uses_original_profile = TRUE;" line in the encoder, so not sure why this issue happens.

Reproducible in 8.12.2 and latest master on windows.