Works fine with google keyboard. You are using microsoft keyboard, if I'm not mistaken?

actually iam using Google's keyboard, but the bug disappeared after i updated the keyboard

Not sure what is the suggestion box. If it is a feature of the keyboard which allows to fill the whole word or to paste a saved password or something else, than it is not supported at all.
It is a platform / keyboard specific feature, and the game only supports regular keyboards (click a button - print a character).