You will see a group of tabs above the block of smilies in the editor window.

These select sets of symbols, which are inserted when the corresponding button in the table is clicked.
The feature is experimental, and I may remove it in future if it does not seem to be useful (but any symbols posted in the meanwhile should remain in posts).
A small sample to the 200-odd symbols available: ??????¢£¥€°®¿???????????