Ask HN: Unknown or expired link?

[pj]

Sometimes I click threads open and read through them and then add my comment. When I do this, I get a single line that says, "Unknown or expired link."

If I refresh, the thread appears and I can post my link.

What is the purpose of this timeout?

[bayareaguy]

This problem stems from a limitation of the way HN maintains state. An earlier post with some links to the problem code is here: http://news.ycombinator.com/item?id=163755

This is a well known problem pg hasn't gotten around to fixing. See YC: "unknown or expired link" -- fix it already (790 days ago) http://news.ycombinator.com/item?id=28944

[pj]

I didn't even realize it was a bug. I can't believe it is so old!