Privacy-centric search engine DuckDuckGo has denounced Google's plans to implement an alternative to third-party browser cookies, which for years have allowed advertisers to track the activity of web users. The company has revealed it will block Federated Learning of Cohorts (FLoC), the proposed replacement, via both its search engine and Chrome browser extension. The DuckDuckGo search engine will disable FLoC functionality with immediate effect, while an update to the browser extension will give users the chance to opt out manually. However, the extension update is currently under review by Google, which vets all new additions to the Chrome Web Store. According to Google, the introduction of FLoC will allow people to benefit from greater levels of online privacy, but without destroying the underlying economics of the web.