#!/bin/bash

curl -Ss 'https://files.openscad.org/' \
| sed '
  s@^.*<a href="openscad-\([0-9.]\+\)\.src\.tar\.gz">openscad-\1\.src\.tar\.gz</a>.*$@\1@
  t
  d
' \
| sort -V \
| tail -n1