This web page already uses highlight.js to highlight code snippets, even though at the time of this writing there are none to highlight. The UI that has been built for writing on this site is already good in the sense that it is small, but as always, comfort is showing at the door, asking for more features.
Writing posts with syntax highlighting would be nice. Would layering a <textarea> with invisible, selectable text, and an inactive container that displays the highlighted text be enough ?
Sure it is (^: