Though correctly represented in the lesson (http://i.imgur.com/6DlvZUV.jpg) hints are (except punctuation marks) not visible in the widget’s edit field once they contain at least one accented Cyrillic letter: http://i.imgur.com/1qA0gRr.jpg
The actual hint here is
кро́ме, за исключе́нием; выпотрошенный
@eugrus - I just checked this and it seems to be working OK over here. Can you try readding the hint again to see if that fixes it?
It won’t: it’s quite an old issue, but I haven’t reported it till now while accenting characters is not too common in Russian.
@eugrus - Strange, I’m not sure why it would be happening on your computer but be working properly for me on the same OS and browser.
If anyone else notices this issue please let us know.