Run exiv2 -vV and then look for enable_bmff - should have a value of 1.
If so, run exiv2 -pp <foo>.CR3 to see if the preview is the regular JPEG or the proprietary Canon HDR thumbnail.
Run exiv2 -vV and then look for enable_bmff - should have a value of 1.
If so, run exiv2 -pp <foo>.CR3 to see if the preview is the regular JPEG or the proprietary Canon HDR thumbnail.