I got the latest master branch, and when I decode the thumbnail for newer cameras such as Sony A73 and Fuji X-H1, thumbnail.tformat still returns LIBRAW_THUMBNAIL_UNKNOWN.

rawProcessor->unpack_thumb() does return LIBRAW_SUCCESS.

Despite getting LIBRAW_THUMBNAIL_UNKNOWN, I go ahead and treat it as LIBRAW_THUMBNAIL_JPEG and I was able to get the thumbnail (preview image) successfully.

I thought those newer cameras are supported in the master branch, so why am I still get LIBRAW_THUMBNAIL_UNKNOWN return code?