The key is public by nature — it travels in the page source. It only works on waldshut.org: a request from anywhere else is served, but never counted.
pk_8716bae78c5b68e91fd9e3b4
<script src="https://relay.mib.news/w.js" data-key="pk_8716bae78c5b68e91fd9e3b4" data-count="4" async></script>