Users getting "pop-ups blocked" in my website

I don't have any "window.open" and have no intentional pop-ups on my website at all.

However, a number of users on different devices and countries seem to be getting "pop-ups blocked" alerts only when using my website, since ~1 or ~2 weeks ago.

This seems to be only happening on Android, using Chrome (includes Chrome from the Play Store, Samsung Browser and stock browser, I believe, based on the version numbers), and different devices (mostly Samsung, but there are cases on LG, Huawei and ZTE).

I have an LG and tried every single browser I could (including Samsung Browser), and I don't get any pop-ups. Other users on Samsung also don't get pop-ups. No complaints from iPhone or Desktop users.

I am extremely careful with coding on my website and I'm pretty sure nothing in my code could create a pop-up. In terms of 3rd party, I include jQuery and Fonts from "googleapis.com" and "jquery.com". I also have Google AdSense and Google Analytics.

If you want to have a look, the website is "similarworlds.com" (we don't show ads at log out).

Have you ever seen this happening before, or do you know what this could be, and how can it be resolved? I'm suspecting a number of users got a Virus, but I can't understand how it suddenly started at the same time and users claim it's only on my website.