This is the authoritative source of the most-widely-used mod: https://deskthority.net/viewtopic.php?f=7&t=2510&start=
This commenter says it started in 2015 (I assume that's accurate),
https://news.ycombinator.com/item?id=27191052
>"Hey @PostThisTooFast, you seem to be shadowbanned based on two flagged comments when your account was new in 2015. Hey @dang, this account has made many good comments since then."
To anyone confused by this thread, look at the "showdead=[yes|no]" toggle in your HN preferences.