Hello,
first thank you for your rersponse.
I finally managed to solve it by following this: https://docs.wppopupmaker.com/article/304-why-is-my-popup-showing-in-the-footer-of-my-site
Indeed, I had a cache plugin on my site, however even tweaking all the minify and cache options (I needed the cache plugin to remain active), I only managed to solve it by following the #3 point of the article.
Thanks anyway, I hope this helps another one.
Sorry, I did’t see that option. However it would be nice if it was setted automatically by default in the pages you have a reference to that popup.
Thanks for the response.