That would be the 1993 restoration of “Snow White and the Seven Dwarfs”, scanned and output at 4K (I believe 10-bit Cineon). No idea if Disney has since done a new digital master, and it wouldn’t surprise me if they have. First new-release 4K DI was 11 years later with “Spider-Man 2”, though VFX were done in 2K.
Interesting, what’s the bet that after their 4K restoration they did what everyone does and did a 2K output to film instead of 4K? Well, if we can find a print from the 70’s/80’s we can do our own 4K scan.