I use Firefox also. At work, I have the popups in Firefox because I have cookies automatically removed every time I close the browser. And yes, (at least one of) it does bypass Firefox's regular pop-up blocker. I'm very certain the ad checks whether a certain cookies exists, and if not, it'll pop-up the ad and generate a cookie.
Try it: remove the cookeis you have relating to "tribalfusion" in th domain, and reload a page in Jref. On next page reloads, it doesn't come up anymore.
Even though the ad comes up once, the fact is there are pop-ups.
Keiichi
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