> Hint: if the last character is not alphanumeric, put a # (a blank URL fragment) to work around HN's autodetection of punctuation

I usually use URL encoding (aka percent encoding) [0] in this case but that’s a pretty neat trick and certainly more convenient than for example pasting the URL into https://meyerweb.com/eric/tools/dencoder/ and pressing the encode button and copying the encoded URL.

[0]: https://en.wikipedia.org/wiki/Percent-encoding