I will answer myself for future reference, if someone needs to use Cloudflare with Discourse.
First: I followed @neil 's guide to add Google Tag Manager in Discourse. Why are we using GTM? We need to fire two Google Analytics tags and ComScore’s tag.
Then, I just created a new Custom HTML tag with the following code:
<script type="text/javascript">
pSUPERFLY.virtualPage(location.pathname, document.title);
</script>
Which fires everytime virtualPageView is invoked. On advanced settings I left the “fire once per event” option.
Here’s a screenshot:
Finally, I added the standard Chartbeat code on the </body> section in the Customize → CSS/HTML admin panel.
That’s it! 