Mozilla has decided to be more vocal about the ways in which Apple, Google, and Microsoft set technical requirements that have hindered development of its Firefox web browser, and therefore harmed competition.

Many of the competitive barriers have been discussed for years - in technical circles, and behind closed doors with regulators. During those years, Firefox's 30 percent of the global browser market share slipped steadily. Today, just over three percent of browser users favor Firefox - the impact of platform rules and of relentless marketing.

With renewed lobbying to level the browser playing field - and the pending March 6 compliance deadline for Europe's Digital Markets Act (DMA) approaching - Mozilla has decided to detail the issues and the harms it feels they cause.

"For years, Mozilla has engaged in dialog with platform vendors in an effort to address these issues," the development group declared. "With renewed public attention and an evolving regulatory environment, we think it's time to publish these concerns using the same transparent process and tools we use to develop positions on emerging technical standards."

Mozilla's concerns are documented in a summary dashboard and GitHub issue tracker that enumerate and explain the technical barriers imposed by rival browser makers that put Firefox at a competitive disadvantage.

At the top of the dashboard - by virtue of alphabetic order and coincidentally by actual importance - is Rule 2.5.6 of the Apple App Store Review Guidelines, which requires that all browsers on iOS use Apple's WebKit rendering engine.

The consequence of that requirement is that all browsers for iOS are essentially Apple's WebKit under the hood - making it hard for developers to differentiate their products.

Lack of browser competition and differentiation on Apple's iOS has been a sore point for Mozilla - and for Google, which drives development of the Chromium browser engine that powers both its own Chrome browser and Microsoft's Edge. Or at least it does on every platform bar Apple’s.

Apple's WebKit rule for iOS is one that regulators in the UK and Europe have investigated - and it may not be around much longer.

Other technical obstacles cited by Mozilla have received less attention despite, its claimed, harming competition.

For example, iOS disallows third-party apps from using Safari's multi-process architecture unless they do so through WebKit. Also, iOS doesn't allow the creation of memory regions that are both writable and executable - yet it makes an exception for WebKit and other Apple applications.

Then there's Apple's iOS accessibility APIs, which Mozilla says are partly undocumented so that other browser-makers have difficulty supporting accessibility web standards.

The list goes on: Messages integration limitations, browser data import limitations, default browser setting and checking limitations, origin-based domain limitations, browser extension limitations, and beta testing limitations.

Google gets called out for failing to allow third-party Android browsers to import browsing data, for sometimes ignoring a user's default browser choice, and for integrating Android with Google Search in a way that makes search results worse when users search with Firefox.

Microsoft is not spared either. The Windows biz stands accused of failing to allow third-party browsers to set themselves as the default browser, for allowing Edge to set itself as the default more easily, and for opening certain features in Edge regardless of the user's choice of default browser.

Further platform parity gaps have been identified in issues posts from members of the internet community.

"People deserve choice, and choice requires the existence of viable alternatives," Mozilla wrote. "Alternatives and competition are good for everyone, but they can only flourish if the playing field is fair. It's not today, but it's also not hard to fix if the platform vendors wish to do so."

Apple, which continues efforts to minimize its obligations under the DMA, did not respond to a request for comment. Nor did Google.

Microsoft replied that it had "nothing to share." ®

https://www.theregister.com//2024/01/25/mozilla_apple_google_browser_wars/