Overview

• On July 29, Opera filed a formal complaint with Brazil’s CADE alleging Microsoft preinstalls Edge as the default on Windows and offers OEM incentives that exclude rival browsers.
• The filing accuses Microsoft of employing manipulative interface tactics—from obtrusive banners to link redirection in Windows apps—to steer users away from alternative browsers.
• Opera notes that despite its status as Brazil’s third-most-popular desktop browser with millions of active users, Microsoft’s practices hinder fair competition.
• The complaint seeks CADE-ordered remedies including open preload rights for PC makers, unblocked browser downloads and an end to dark-pattern UI designs.
• This action builds on Opera’s July appeal under the EU Digital Markets Act and recalls its 2007 EU antitrust complaint that led to a €561 million fine for Microsoft’s Internet Explorer bundling.