I would be very surprised if Firefox added support. They have been very reluctant to include any additional image formats that weren't developed by Mozilla empl

I would be very surprised if Firefox added support. They have been very reluctant to include any additional image formats that weren't developed by Mozilla employees. See for example WebP and Jpeg2000. Their reasons being things like added security risk, lack of demand, lack of support in other browsers, patent risk etc, which all apply just as much to this format.