Mozilla intends to add basic ad filtering capabilities to its Firefox browser later this year, according to its recently updated roadmap.

The move follows from what Asa Dotzler, Firefox roadmap and community leader at Mozilla, describes as changes that are making the web experience worse.

"Trackers, intrusive ads and other dark patterns threaten to drive people away from the open web and that's not good for people browsing or publishing," he says in Firefox roadmap update made on Thursday.

"Over the next year or so, Firefox will take a stand against tracking, intrusive ads, and other dark patterns on the web by blocking the worst content and more clearly communicating the privacy and other protections the browser offers."

In so doing, Firefox follows Opera, which comes with a built-in ad blocker, and Chrome, which just started gingerly filtering intrusive ads, the subset of online adverts that violate The Coalition for Better Ads' guidelines. Apple's Safari might qualify too if you count Reader mode, which simplifies webpages to make them more readable, often ditching ads in the process.

Dotzler's choice of the term "ad filtering" rather than "ad blocking" or the broader "content blocking" suggests Mozilla aims to follow in Google's cautious footsteps as it navigates the conflict between privacy-starved, ad-averse users and revenue-starved, anything-goes publishers and advertisers.

As Mozilla notes in its 2016 annual report, the majority of Mozilla Corporation revenue that year came from Firefox search partnerships and distribution deals around the world. Global ad powerhouse Google is one of those partners and Mozilla has shown it isn't inclined rock the boat too much.

Moral unease

Mozilla did just take a stand of sorts by pausing its Facebook advertising in the wake of the Cambridge Analytica scandal. But the fact that it was advertising on Facebook at all suggests that, at least up until now, the marketing benefits outweighed any ostensible moral unease.

In November 2017, Mozilla said Google would be Firefox's default search provider in the US, Canada, Hong Kong and Taiwan. So while Mozilla may be willing to allow Firefox to nibble on the hand that feeds it, it isn't likely to help it clamp down through the indiscriminate blocking of all ads, even if technically savvy users can achieve as much with Firefox add-ons.

The ad filter, as Dotzler describes it, will prevent the display of certain types of ads by default. "Firefox will offer users a simple ad filtering option," he explains.

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In an email to The Register, Peter Dolanjski, product manager of Firefox, said the roadmap describes future plans, some of which are still in the early stages of development

"We are researching and, in some cases, developing various methods of blocking invasive forms of advertising," he said. "This includes: autoplaying videos with sound (public discussion here), in-content pop-ups (add-on to report examples here) and a variety of other deceptive practices (listed here). While these methods are based on ad and content types, our final approach will be announced at a later date. We expect to integrate this functionality directly into Firefox."

Firefox, Dotzler suggests, is becoming more "opinionated," a characterization encompassing a variety of planned advertising and tracking controls.

The browser is also slated to get other updates related to performance, personalization, and mobile device capabilities. But it's the opinionated features being planned that are most likely to distinguish Firefox from its competitors.

Beyond ad filtering, there are plans to block ad retargeting (cross-domain ad tracking), to centralize privacy controls, and to provide more fine-grained protection against tracking tech.

Global permissions management for location, audio, camera, and the like is also being considered, to block videos from playing automatically. There's even the possibility future versions of Firefox will provide alerts if a visited website has been breached. ®