• Mozilla says Firefox’s future is at risk.
• OpenAI and Yahoo are interested in Chrome, but Mozilla warns fixes may come too late.

Firefox’s future may hang in the balance as the US Justice Department pushes for remedies to limit Google’s dominance in the search market, The Verge reported. In a court hearing on Friday, Mozilla CFO Eric Muhlheim testified that the proposed changes could seriously impact the organisation’s ability to operate its flagship browser. “It’s very frightening,” he said.

Among the DOJ’s proposals is a ban on Google paying to be the default search engine in third-party browsers like Firefox. The proposal is part of a broader antitrust case in which a US federal judge ruled that Google violated antitrust laws by maintaining monopolies in both general search and search advertising. Judge Amit Mehta found that Google used exclusionary agreements—particularly with Apple and Android device makers—to suppress competition and maintain its position as the default search engine across platforms. Although some of the DOJ’s narrower advertising claims were dismissed, the ruling underscored Google’s ability to raise ad prices due to limited competition. Remedies are expected later this year and could include structural changes or even a forced sale of part of Google’s search business. Google has said it plans to appeal.

Mozilla, which competes directly with Google’s Chrome browser, says it may not survive the impact of losing Google’s default search payments. Muhlheim told the court that Firefox currently generates around 90 per cent of Mozilla’s revenue, and about 85 per cent of that funding comes from its agreement with Google. If those payments were to stop, Mozilla would be forced to make major cuts across its teams—including product engineering—and risk falling behind in development. Muhlheim warned this could lead to a “downward spiral” of fewer users, lower revenue, and potentially the shutdown of Firefox altogether.

The consequences could extend beyond just one browser. Mozilla’s nonprofit arm, the Mozilla Foundation, relies on revenue from Firefox to support projects like open-source web tools, internet privacy research, and studies into how artificial intelligence can be used for public benefit. A loss of funding would also affect these initiatives, which aim to keep the web open and accessible outside of commercial influence.

Muhlheim argued that such an outcome would run counter to the DOJ’s broader goals of increasing competition in the browser and search markets. He pointed out that Firefox’s browser engine, Gecko, is the only major engine not owned by a large technology company. The others—Google’s open-source Chromium and Apple’s WebKit—underpin the majority of browsers on the market today. Mozilla developed Gecko in the early 2000s as a response to concerns that Microsoft’s Internet Explorer could become the gatekeeper of web standards. The engine ensures browser interoperability and has long been positioned as an alternative to the commercial infrastructure dominating the internet.

While Mozilla has focused on maintaining its own browser and engine, others in the tech industry have shown interest in expanding their footprint if the court requires Google to divest parts of its business. Companies like OpenAI, Yahoo, and Perplexity AI have expressed interest in acquiring the Chrome browser if it’s put up for sale. Yahoo has said owning Chrome could boost its search market share, while OpenAI and Perplexity see potential in using Chrome as a distribution channel for AI-driven search tools. Mozilla has not expressed any interest in acquiring Chrome. Google, for its part, opposes the idea of selling Chrome, warning that it could harm the broader Chromium-based ecosystem and raise security and privacy concerns for users. A final decision on potential remedies is expected after the trial concludes on May 9.

In the meantime, replacing the revenue Mozilla currently receives from Google poses a challenge. While discussions with Microsoft have taken place around making Bing the default search engine in Firefox, Muhlheim said the economics of such a deal would be very different. Without Google’s participation in the bidding process, Mozilla would have less negotiating leverage. Additionally, the company has found that Bing doesn’t monetise user searches as effectively, resulting in lower revenue per search.

Mozilla has tested these alternatives in the past. From 2014 to 2017, it switched Firefox’s default search engine from Google to Yahoo, but many users responded by switching browsers altogether. In a more recent internal study conducted from 2021 to 2022, Mozilla tested a quiet switch from Google to Bing among some users. The results showed a drop in engagement and revenue, reinforcing concerns that such a change could hurt the organisation’s financial stability.

The DOJ’s proposals aim to create a more level playing field by allowing new or smaller search engines to compete for default positions on browsers. But according to Muhlheim, the development of a viable, high-quality alternative to Google’s search engine will take time—possibly years. He warned that Mozilla might not be able to wait that long without cutting resources and restructuring the organisation. “We would be really struggling to stay alive,” he said in court.

On cross-examination, the DOJ pressed Muhlheim on Mozilla’s business model. He acknowledged that relying on one partner for the vast majority of its revenue is risky, regardless of the trial’s outcome. He also agreed that other browser companies, like Opera, have found ways to grow revenue through advertising rather than relying on search engine deals. However, he pointed out that Mozilla’s strong privacy stance may limit its ability to pursue the same strategy, as much of the online ad business relies on tracking and user data—something Firefox avoids.

Mozilla has supported browser choice screens at the operating system level, which prompt users to select a browser when setting up a new device. But it doesn’t endorse similar choice screens within browsers for search engine selection. Muhlheim explained that Firefox already offers multiple search engine options through its interface, giving users flexibility without forcing a selection screen. “There are a thousand different search points in the browser,” he said. “Choice is a core value for us, but context matters. The best way to get to choice is not always a choice screen.”

As the trial moves toward a decision on remedies, Mozilla’s leadership is watching closely. Judge Mehta asked Muhlheim whether Mozilla would benefit from the presence of a strong competitor to Google in the search market—one that could match its quality and monetisation power. Muhlheim agreed. “If we were suddenly in that world,” he said, “that would be a world that would be better for Mozilla.”