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Adblockers stop publishers serving ads to (or even seeing) 1bn web users - Press Gazette
(pressgazette.co.uk)
This is a most excellent place for technology news and articles.
There are a couple of steps missing at the beginning. There was a time when we only blocked popups; other types of ad were fine, but popups were annoying enough that they needed special attention, and the popup-blocker was usually built-in to the browser without needing an extension. It took a couple of years for the non-popup types of ads to become obnoxious enough to warrant blocking.