Poor Consistency in CJK Typefaces
Instead of using their own hardcoded font, Duolingo seems to rely on user fonts to display CJK (Chinese, Japanese, and Korean) text. I recommend they decide on a dedicated (set of) font(s) for those languages, likely Noto Sans/Serif.
Oooh, thank you. I just downloaded and installed all of Noto.
I have been a Unicode nerd since version 1. In fact, I played a critical role in getting Unicode Web domains standardized and deployed when half of the IETF group was saying we had to do it instantly, and half was saying it was impossible.
I'll be back after I get a chance to test them all.