From: Zak Seidov <zakseidov@mail.ru> Subject: [math-fun] Dario Alpern's QUAD ... https://www.alpertron.com.ar/QUAD.HTM

They say that Java is obsolete(?) and I should do something that I don't understand:( I use Win XP and Win10 if it matters.

The site says "This page uses JavaScript, ..." and after allowing that it works for me (Firefox 45), no need for Java.