Card Hunter is now properly secure, i.e. if you visit: https://game.cardhunter.com you will receive the game and all data via secure https. Oh, and also, the Halloween content is gone for another year!
It appears to be closed on both, so probably yes. This, however, is definitely a non-definitive response.
Sorry for my ignorance, but which is the difference to play at http vs https?. Is there some improvement or something to have in mind for choose one or other?
Https uses secure socket layer encryption. Many browsers warn against typing anything on an unencrypted page, and in some cases it takes effort to get around it.