I would like to give some feedback about ...

From: https://checkio.org/mission/most-wanted-letter/solve/

HTTP_USER_AGENT:

Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:46.0) Gecko/20100101 Firefox/46.0

When i check my solution with the try it function, for example the String "One" the result is always right, giving an e as wanted in the solution. But when i Run&Check it the solution is always 'O' or 'n' what is given as wrong. So there seems to be some different behaviour between these to functions.