So duolingo just changed its design to some 2004-paint thing; and the forum is still beautiful with the round flags and easy-to-read interface.
Beyond personal preference the lessons too are worse with this change; the chubby fonts and everything detract from the meaning and so on (although this is not a good explanation at all e.e).
So twitter changed many months back, but I still use the old one; there is the option to choose there. I found no option on the settings; much less the panel informing about the change having an option to choose.
So I just have to deal with it or is there a way to use the old design?