Firefox helps iPhone users bypass ads on web sites while making money showing its own ads

Mozilla has recently introduced an ad-blocking feature to its iOS version of Firefox browser, offering iPhone users a way to bypass ads on various websites while still displaying its own ads. The feature, which has moved out of the experimental phase, was officially launched by Mozilla on Tuesday. This decision came after Mozilla found it necessary to rethink its approach to ad-blocking on iOS due to architectural differences between iOS and other operating systems.

Apple's WebKit Content Blockers were incorporated into Mozilla's iOS Firefox version to enable ad blocking. Unlike traditional ad blockers, WebKit Content Blockers live in bytecode format, executing for each resource request and modifying requests or injecting CSS changes. This approach was chosen by Apple to address performance drawbacks associated with JavaScript-based content blocking extensions.

Ad blocking in Firefox for iOS is currently turned off by default, and users can enable it by navigating to the in-app settings menu, tapping on Browsing, and toggling the Ad Blocker field on. This feature blocks ad-related trackers, ads from third-party advertising networks, third-party ads served by websites, and popups/overlays, but it does not eliminate ads on search result pages or sponsored content on Mozilla's own pages.

Currently, the ad-blocking feature in Firefox for iOS is available gradually, and the general release to all users is dependent on its initial rollout performance. Mozilla has not specified a timeline for the full rollout. The company emphasizes that it values the ad-blocking ecosystem and will continue to support it, but it has no plans to expand built-in ad-blocking outside iOS at this time.