Hey there,
It's on the list.
My guess you need to clear or clean up the cookies in your computer. This is usually the case for most dysfunctions from the forum.
You can also type out the content rather than go on the smiley list, the content code for that smiley is:
" :icon_scratch " <--- I didn't close it. Make sure to close the content with the colon '
:'key. Most of the smilies can be written if you remember the codes, example :cupofcoffee: