There are a few particular items in our Github issue tracker, that I thought would make for good first issues for people who haven't coded for LessWrong yet (or have only done so a bit).
(In general, you can find recommended issues by filtering by the "good first issue" tag)
- Sharing a draft with someone should cause that post to appear in their drafts (on their user profile)
- Downvoted posts should still appear on the author's Profile page
- Messaging a person shouldn't create a new conversation if you already have an untitled conversation with that person (this may be slightly trickier as a first-issue but still pretty manageable)