Did you find out in the end? In next update, the clue will be phrased in a slightly less misleading way. I can assure you it is nothing as subtle as the grass ;)
The new clue will be phrased like that 'AS IF I WOULD SHARE MY CODE TO ANYBODY AHAH' Remember what the smalley in level -1 was saying ? Take it together with what the smalley is saying
Also there is an additionnal clue in level 5/-2 hidden somewhere
