I know I've seen this question on the forums before but a quick search didn't answer my question.
There used to be line numbering and syntax highlighting built into wordpress' theme and plugin editors. Then this functionality disappeared. Not only that, but none of the plugins for this seem to be compatible with wordpress 3. There's one called 'power code editor' that doesn't have page numbers, doesn't highlight css that much and throws up false red syntax error highlighting. This was the best I could find.
What happened to syntax highlighting and how do I get it back? Also, what else is useful for editing theme and plugin code directly through wordpress?