Correct me if I am wrong, but the 9th digit of UNO wallet was always merely 'cosmetic'.
I could build one with cosmetic 9th digit right now but it seems pointless to have it there.
I don't think so. It was actually functional. I recall testing it and being amazed it really worked. Blockexplorer and txs were able to handle other number than zero on 9th place and did actually work as far as i remember. So, no, to my remembering was not just cosmetic but an actual feature.
I've never seen 9 decimals in any explorer or transaction. I recall it being nonfunctional.