Firefox on iPhone Now Blocks Ads, Just Not Mozilla's
Firefox on the iPhone now blocks ads by itself. Mozilla has switched on a built-in ad blocker in the iOS app, built on Apple's WebKit Content Blocker interface and the EasyList filter list, and it stops third-party ad networks, ad trackers, pop-ups and overlays before they load. Two things are worth knowing before you go looking for it: it is off until you turn it on, and it deliberately leaves Mozilla's own advertising alone.
What it blocks and what it is built on
The blocker works at the network level, so the requests are refused before the page renders rather than hidden afterwards. Its target list is the usual third-party layer: advertising networks and exchanges, the trackers that ride along with them, and the more aggressive formats such as pop-ups and full-page overlays. The filtering comes from EasyList, the same community list that sits underneath most desktop blockers, and the plumbing is Apple's own content-blocker API, the one Safari's ad blockers use.
It is off by default: where the switch is
Mozilla shipped this as an option rather than a new default, so a fresh install behaves exactly as before until you go into settings. The path is Settings > Browsing > Ad Blocker. There is also a per-site control in the site menu while you browse, which is the one you actually need when a page misbehaves and you want to check whether the blocker is the reason.
What stays on your screen
- Ads the site serves itself: first-party advertising is untouched. If a publisher hosts its own banners, they load.
- Ads in search results: the sponsored entries above search results are outside what this blocks.
- Mozilla's own sponsored content: the sponsored shortcuts and promotional tiles that Firefox itself shows on a new tab are explicitly excluded.
That last one is the honest asterisk on the announcement. Mozilla sells those placements, and the blocker it ships does not touch them. It is not hidden, the company says so in its own post, but it does mean the feature is a blocker of other people's advertising.
Why this had to come from Mozilla
On iOS every browser renders with WebKit, and the extension ecosystem that carries blockers on desktop does not exist in the same form. That leaves two options for someone who wants ads gone on an iPhone: a separate content-blocker app that plugs into Safari, or a browser that does the filtering itself. Firefox has now taken the second route, which removes the step where you install something extra and hope it is trustworthy. On a platform where you cannot bring your own blocker, the browser vendor deciding to include one is the whole ballgame.
Two directions at once
The timing is hard to ignore. A day earlier, Google finished clearing the last Manifest V2 extensions out of its store, and the full uBlock Origin stopped being installable in Chrome. In the same week, the two big non-Chrome browsers moved the other way: Brave kept hosting the old blockers itself, and Mozilla put blocking into the product on the platform where extensions cannot reach.
For anyone who cares about tracking rather than clutter, that is the practical reading of the week. The layer that used to be a browser add-on is turning into a feature of whichever browser you picked, and the choice of browser now carries more weight than the choice of extension. Where filtering is not available in the browser at all, the remaining option is a level lower, on DNS, in the router or in the network app on the device.
