For me, the most important thing is a reminder of what exactly you are sending as you’re about to post:
- ＋ Create Topic
- ⮌ Reply
Message ← the only one that’s the same in the composer for a new vs. existing message👁̸Whisper
vs. the CTA links outside the composer:
- ＋ New Topic
- New Message
Brevity is the soul of good UX. 