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Mozilla working on in-page popup blocker for Firefox

The days of native popups in browsers are long gone, but sites still frequently use in-page alerts like the one above. They are completely useless most of the time, and usually violate the Better Ads Standards (potentially causing the site to lose revenue from Chrome users ). While Firefox isn't outright blocking ads on some sites like Chrome is, the browser's developers are working on a blocker for these popups.