I was pretty confused by the fact that the : grin : ( ) icon didn't appear, but I pinpointed it to the appearance of Apple ][ before, because the square brackets.
:grin: <- now not shown.
Just for your information. :)
No emoticon is shown now.
Let us see, if now appear Apple ]
So the bug is that once an open square bracket appears then no emoticon is shown until a close square bracket appears.