Sometimes a picture is worth a thousand words, but even when it's not, you can still use 'em. After popping up in chat and Messenger windows in the past, Facebook is employing stickers in comments for both mobile and the web. Use the small pictures to visualize your reaction to Timeline, Group and Event posts when you'd rather keep things succinct. Unfortunately, if you want to express your feelings with an image for a regular post, you'll still have to upload one the old fashioned way.