Chrome Manifest V2 Ends, Ad Blockers Like uBlock Origin Face Demise

With the next update to Google Chrome, the last remaining workaround for Manifest V2-based extensions will be removed. According to reports from Slashdot and 9to5Google, this will render traditional ad blockers, particularly uBlock Origin, effectively unusable.

Extension Compatibility Called into Question

A commit to the Chromium repository noted by CyberNews removes support for the “kExtensionManifestV2Disabled” flag. This code is described as “dead code” by Google developers, reflecting that Chrome no longer officially supports Manifest V2 extensions.

This flag effectively served as a loophole for continuing to use Manifest V2-based extensions. However, a Google developer who commented on the commit explained: “MV2 extensions are no longer allowed on all supported versions of Chrome. Due to complexity, technical debt, and security risks, we cannot provide and maintain this feature indefinitely. In fact, we have recently discovered several bugs specific to MV2. Of course, other browsers can continue to support it if they wish.”

Security and Technical Debt Perspectives

Google officially cites improved security as the reason for pushing the deprecation of Manifest V2. Manifest V3 restricts extension permissions, in particular prohibiting the execution of remotely hosted code. The company claims this reduces the risk of malicious extensions intercepting user data.

However, critics have long pointed out that this change is intended to deliberately weaken ad blockers. Manifest V3 significantly restricts the methods of blocking network requests that were possible in Manifest V2. Specifically, it requires the use of the declarativeNetRequest API, and the number of rules is strictly limited.

As the Google developer notes, the existence of “technical debt” that must be maintained suggests the complexity accumulated over years in the Manifest V2 codebase. According to the company, this debt and security risks are the basis for the final deprecation.

Scope of Impact and Timeline

The impact of the deprecation is not limited to Google Chrome. According to Neowin, other Chromium-based browsers such as Microsoft Edge and Opera are also likely to take similar measures. However, as the Google developer explicitly stated in the comment, each vendor retains the option to continue supporting Manifest V2 on their own.

Chrome 150 is scheduled for release later this month, and this version will remove the related flag. Remaining Manifest V2 code is expected to be completely removed in Chrome v151. Manifest V2 extensions currently used by users, including uBlock Origin, will stop working after the update.

As an alternative, Manifest V3-based ad blockers such as uBlock Origin Lite are already available. However, these extensions have limited filtering capabilities, particularly in terms of dynamic rule management and applying complex filter lists.

Browser Market Fragmentation and Choices

The deprecation of Manifest V2 has once again drawn attention to user options in the browser market. Mozilla Firefox has implemented parts of Manifest V3 but has indicated a policy of maintaining ad blocker functionality. Brave Browser also enhances its built-in ad blocking features and maintains its own extension system while being Chromium-based.

Google Chrome holds about 65% of the global browser market share. The deprecation of Manifest V2 is also an important issue for corporate IT administrators, as it may impact employee browser policies and enterprise network security management.

Meanwhile, Google’s business model relies heavily on online advertising. The aspect of restricting ad blockers contributing to revenue cannot be denied. The company is promoting its Privacy Sandbox initiative, which aims to balance privacy protection and advertising effectiveness, but industry evaluations remain divided.

Editorial Opinion

In the short term, after the release of Chrome 150, the inability to use numerous extensions including uBlock Origin may cause confusion. Particularly in environments where browser policies restrict extensions within companies, administrators will need to quickly prepare alternative solutions. Whether Microsoft Edge and Opera will follow suit depends on each company’s user base and policy decisions. Given that Opera has its own built-in ad blocker, it is unclear whether it will immediately follow.

In the long term, this change serves as an opportunity to reaffirm the importance of diversity in the browser market. As Google’s dominance grows, the significance of independent browsers like Firefox and Brave may be reevaluated. Furthermore, a fundamental question arises about how much a single vendor’s commercial interests should affect user choices in the standardization process of web technologies. For website operators relying on AdSense and other ad revenue, the debate over the balance between tracking and privacy will continue.

From an editorial standpoint, we need to keep a close watch on which aspect—the security improvements of Manifest V3 or the restriction of ad blocking functionality—should be given more weight. Evidence that Manifest V3 contributes to security improvements to the extent Google claims is limited, and suspicions linger within the industry that the primary purpose is protecting advertising revenue. What constitutes an ideal browser for users, and whether options should remain in the market, are matters that require debate.

References

• Google Chrome’s Next Update Will Mark the End of Popular Ad Blockers - Slashdot
• Google Chrome removing Manifest V2 flag, killing remaining extensions - 9to5Google
• Chromium Gerrit Commit - Remove kExtensionManifestV2Disabled