Today's update of Telegram Desktop is all about emoji and stickers:

— all the existing emoji are now supported, you can see them in the emoji panel (almost 500 were added)

— on the stickers panel you have a settings button now (in the lower right corner) where you can reorder and manage your sticker packs — the order will be automatically synced between all your Telegram devices (after updating the apps there to the latest versions as well)

— you can press-and-hold on a sticker in the stickers panel to see the preview (how this sticker will look when you send it), you can move the mouse while pressing and see the near stickers previews as well

You can update your Telegram Desktop to the latest 0.9.15 version in Settings or download it from https://desktop.telegram.org