So, I skimmed the article and may have missed it. Why is this anything more that tinkering with and (maybe torturing) mice? What’s the actual scientific value here? (Assuming invisibility potion wasn’t an actual goal)
Perhaps medical dyes for imaging?
They applied a yellow, food-safe dye to the skin of the mice and found it caused light to refract in such a way that their skin became significantly more transparent. An article I read (I did not read this one) listed some potential uses like making veins visible for blood draws and more precise tattoo removal. The dye washed off afterwards.