Ask HN: Why some usernames in Hacker News are green?

I can't find a pattern, please help me understand.

Because they're newly created accounts.

Interesting. I created a throwaway account to ask a question on HN (through submit button).

I am able to access it only through my throwaway account but I don't see it in regular HN feed or in Ask HN tab. Any idea of the reasons? New accounts have to wait for sometime before Submitting stuff?

No, there is no waiting period that I know of. Perhaps it just got "buried"? HN sees a LOT of traffic. If it isn't upvoted or replied to fairly quickly, it often falls way off the front page quickly.

Thank you.

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