Mozilla says Microsoft is using Copilot and Edge to repeat the anticompetitive tactics that defined the 1990s browser wars, this time with AI as the prize rather than the web.
On April 10, Mozilla went public with an accusation that will feel familiar to anyone who lived through the Netscape era: Microsoft, the company argues, is weaponizing its control of Windows to crowd out competitors in the emerging AI market. The specific target is Copilot, which Mozilla says is being forced onto users through deceptive update mechanisms while system settings are quietly manipulated to make alternatives like Firefox function less reliably. Mozilla timed the statement to coincide with the launch of Firefox 148, which ships with a built-in AI toggle letting users disable AI features entirely. The message is hard to miss: if Microsoft won't give you a choice, we will.
The browser wars comparison is pointed, not hyperbolic. In the late 1990s, Microsoft bundled Internet Explorer with Windows at no cost and used OEM agreements to freeze out Netscape, eventually drawing a landmark antitrust ruling. Mozilla is explicitly saying Microsoft is running "the same playbook," updated for 2026. The mechanism this time involves machine learning-driven update pipelines that push Windows 11 version 25H2 aggressively, embedding Copilot deeper into the OS with each cycle and leaving users with narrowing options to roll back or opt out.
Mozilla isn't the first to raise the alarm. Opera filed a formal antitrust complaint with Brazil's Administrative Council for Economic Defense, CADE, back in July 2025, citing persuasion tactics and dark patterns designed to steer users toward Edge. Brazilian regulators followed up in February 2026 by opening an investigation into Microsoft's Jumpstart Program, probing whether the company was pressuring hardware manufacturers to bundle Edge exclusively and limit browser choice screens. That Brazil is leading the regulatory charge matters: if CADE rules against Microsoft, it could force a structural separation between the OS and AI services, echoing the browser ballot settlements the EU extracted from Microsoft in the 2000s.
What makes this fight categorically different from the original browser wars is what's actually being contested. Market share in a browser was about ad revenue and distribution leverage. What Microsoft is pursuing now is control over the AI inference layer itself. Every interaction routed through Copilot on a Windows machine is a data point, a monetization opportunity, and a reinforcement of user habit. By making Copilot feel as native and unavoidable as the taskbar, Microsoft is trying to establish a default AI gateway before standards, regulations, or rival products can gain enough traction to matter. Reports from April 11 indicate Microsoft is actively removing Copilot branding from standalone apps like Notepad and Snipping Tool, folding the functionality deeper into the OS kernel where it becomes structurally harder to isolate or replace.
Edge's global browser position is actually third, behind Chrome and Safari, which makes the aggression harder to explain on browser market share terms alone. The play is clearly about AI infrastructure and the behavioral data that comes with it, not about winning a tab-count competition. Microsoft is betting that whoever owns the OS interaction layer in 2026 will own the AI relationship with users for the next decade, the same way Google's search default deals have compounded into an almost unassailable ad business.
For the companies competing with Microsoft, the strategic options are limited. Mozilla's AI kill switch is a principled product move, but it relies on users actively choosing Firefox over a pre-installed, deeply integrated alternative. That's a hard behavioral shift to drive at scale. Regulatory action moves slowly enough that by the time CADE or any other body issues a meaningful ruling, Copilot could be as structurally embedded in Windows as the registry. The more significant pressure may come if the EU or US DOJ decides this pattern of conduct warrants fresh scrutiny, particularly given that Microsoft is already navigating ongoing antitrust attention related to its OpenAI investment and cloud AI bundling practices.
Watch how OEM relationships evolve over the next two quarters. If hardware manufacturers start pushing back on Jumpstart requirements, or if a major market forces a choice screen for AI services the way Europe forced browser choice screens, Microsoft's integration strategy hits a real obstacle. Until then, Mozilla is making a principled argument that the industry and regulators should take seriously, even if the outcome is far from decided.
