Firefox iOS gets built-in ad blocker using Apple WebKit API
▼ Summary
– Mozilla has introduced a built-in ad blocker for Firefox on iOS, utilizing Apple’s WebKit technology and the EasyList filter.
– The feature is disabled by default and cannot block site-hosted ads or search result advertisements due to API limitations.
– Firefox lags behind competitors like Brave and Opera in offering this functionality because all iPhone browsers must use Apple’s WebKit engine.
– Although the Digital Markets Act allowed alternative engines in the EU since March 2024, no rival browser has shipped a non-WebKit engine yet.
– Mozilla cited the high cost of maintaining dual browsers as a reason for not developing its own engine, despite Microsoft showing performance benefits for Blink.
Firefox on iOS now includes a native ad-blocking feature, leveraging Apple’s WebKit content blocker technology. This update, which rolled out with Firefox 155, marks a significant shift for the browser on Apple’s mobile platform. The functionality relies on the community-maintained EasyList filter but remains disabled by default, requiring users to manually activate it through the settings menu.
This development arrives years after competitors like Brave, Opera, and Vivaldi already integrated similar protections into their iOS applications. Desktop users have enjoyed extension-based blocking for even longer. The delay stems from the fundamental architecture of web browsers on iPhones. Every app on the device must render pages using Apple’s WebKit engine. Consequently, Firefox on iOS is essentially a different user interface layered over Apple’s underlying code, rather than a standalone engine as seen on macOS or Windows.
The European Regulatory Landscape
The regulatory environment in Europe offers a different technical reality. In March 2024, Apple introduced BrowserEngineKit to comply with the Digital Markets Act (DMA). This framework allows developers to ship alternative browser engines within the European Union, starting with iOS 17.4. Despite this opening, no rival engine has successfully reached European iPhone users since its introduction.
Both Google and Mozilla have developed prototypes for their own engines. However, neither company has released them for public use. Mozilla cited the operational burden of maintaining two distinct browser versions as a primary deterrent. At the time, a spokesperson explained: “a burden Apple themselves will not have to bear“. Microsoft has also explored alternatives, testing a Blink-based prototype that demonstrated superior performance benchmarks compared to WebKit.
Limitations of the New Feature
While the new ad blocker is a notable addition, it operates under strict constraints defined by Apple’s API. It cannot block advertisements served directly by the website itself. Additionally, ads embedded within search results remain visible, and Mozilla’s own sponsored shortcuts are managed separately from this system. These limitations highlight the difference between a comprehensive blocking solution and one constrained by platform rules.
Advocacy groups argue that Apple has failed to provide a truly compliant solution despite having ample time. Alex Moore, director of Open Web Advocacy, stated: “Apple has had more than two years to produce a compliant solution“. This criticism comes as Apple faces ongoing legal scrutiny, including a recent loss at the General Court regarding its gatekeeper designation.
Despite the lack of alternative engines reaching consumers, the release of this built-in blocker demonstrates Mozilla’s ability to maximize existing tools. This timing is particularly relevant given that Google Chrome recently disabled Manifest V2 extensions, including popular blockers like uBlock Origin, on its desktop platform.
(Source: The Next Web)