Chrome will kill uBlock Origin: goodbye to Manifest V2 extensions

Google has announced that starting with Chrome 150 (stable expected on June 30, 2026), it will remove the ExtensionManifestV2Disabled flag, permanently disabling all extensions based on Manifest V2. This includes uBlock Origin, the popular content blocker, and thousands of extensions that have not yet migrated to Manifest V3. The move, anticipated since 2019 when Google published the first draft of Manifest V3, culminates a gradual process that began with the removal of support for V2 extensions in the Chrome Web Store starting June 2024. With this decision, Google definitively closes the door on an extension model that allowed granular control over network traffic, affecting not only ad blockers but also security, privacy, and automation tools.

Why is this important?

Manifest V3 is Chrome's new extension framework, supposedly designed to improve security, performance, and privacy. However, it imposes strict limits on the webRequest API, which allows extensions like uBlock Origin to intercept and modify network requests in real time. Instead, it encourages the use of declarativeNetRequest, which only allows a limited number of predefined rules (currently 30,000 per extension, compared to unlimited in V2). This drastically reduces the ability of blockers to filter complex ads and trackers. According to Google's own data, 85% of active extensions in Chrome have already migrated to V3, but those that haven't represent a significant part of the ecosystem, including extensions with over 10 million users like uBlock Origin. The company argues that V3 improves security by preventing extensions from accessing browsing data indiscriminately, but critics like uBlock Origin developer Raymond Hill point out that the restrictions are arbitrary and not based on evidence of real abuse. In fact, a 2023 study by Princeton University showed that malicious extensions are more likely to use more permissive APIs in V2, but also concluded that V3 restrictions disproportionately affect legitimate privacy tools.

Impact on users and businesses

• Users: will lose protection against invasive ads, malware, and tracking. uBlock Origin, the flagship extension, will stop working. Alternatives like uBlock Origin Lite (based on V3) offer less functionality: for example, they cannot apply dynamic rules or advanced cosmetic filters. According to industry estimates, more than 200 million Chrome users rely on ad blockers, and a 2025 Statista survey indicated that 60% of them would consider switching browsers if functionality is lost.
• Developers: must migrate their extensions to V3, which involves redesigning complex logic that depended on webRequest. Google has provided tools, but many extensions will not be able to replicate all their capabilities. For example, security extensions that analyze traffic in real time to detect phishing or malware see their effectiveness limited. The migration cost for small developers can be prohibitive, and some have chosen to abandon development.
• Advertising and tracking companies: benefit indirectly by reducing blocking capabilities, increasing the effectiveness of ads and data collection. Estimates from the Interactive Advertising Bureau (IAB) suggest that ad blockers cost the advertising industry more than $50 billion annually in lost revenue. With V3, the blocking rate is expected to decrease, benefiting giants like Google (which gets 80% of its revenue from advertising) and ad networks like Meta and Amazon.

Long-term consequences

Google's decision consolidates its control over the Chrome extension ecosystem, which dominates more than 65% of the browser market according to StatCounter. This could accelerate user migration to Chromium-based browsers that maintain V2 support (like Brave or Vivaldi) or to Firefox, which has promised not to adopt the same restrictions. Brave, for example, already includes a built-in ad blocker that does not depend on extensions, and has seen a 15% increase in its market share since Google announced the removal of V2. Vivaldi, for its part, has confirmed it will maintain V2 support indefinitely. Firefox, although with a 3% desktop market share, could benefit if users seek alternatives. An increase in the use of network-level blocking tools like Pi-hole, which filters ads at the router, is also expected. However, these solutions require technical configuration and are not accessible to the average user. In the long term, the move could fragment the web ecosystem, with sites that rely on ads seeing less revenue if users migrate to browsers with built-in blocking, while Google strengthens its dominant position by controlling both the browser and the advertising market.

"The removal of Manifest V2 is not just a technical change, but a decision that redefines the balance of power between users, advertisers, and platforms," says TheVortiq analyst. "It's comparable to when Microsoft integrated Internet Explorer into Windows, but in this case Google is using its control of the browser to favor its advertising business."

What should readers know?

• The deadline is June 30, 2026. After that, V2 extensions will be automatically disabled and cannot be reinstalled.
• uBlock Origin will not migrate to V3; its developer recommends using uBlock Origin Lite, which is less powerful. However, alternatives like AdGuard have migrated to V3 with reduced functionality, and Ghostery plans to do so in 2026.
• Alternatives: switch to Firefox (which supports V2 extensions and has its own blocker), Brave (with built-in blocking), or use DNS-level blockers like NextDNS or AdGuard DNS. You can also install V2 extensions in Chromium-based browsers that support them, like Brave or Vivaldi, although Google has indicated it could pressure these browsers to also adopt V3.
• Google claims V3 improves security by limiting access to browsing data, but critics point out that it also limits innovation and privacy. A 2024 EFF study concluded that V3 offers no significant security improvements over V2, and that the restrictions are designed to protect Google's advertising business model.

In summary, the removal of Manifest V2 is a milestone in Chrome's evolution that affects millions of users and developers. Although Google argues it is for security, evidence suggests that commercial interests play a key role. Users should prepare for the change by exploring alternatives before the deadline.