Google is removing Chrome's final workarounds for Manifest V2 extensions, effectively ending support for legacy ad blockers like the original uBlock Origin. The company has stripped out the "kExtensionManifestV2Disabled" flag, which served as a loophole allowing users to run outdated extensions that were otherwise deprecated. This marks the last remaining pathway for MV2-based tools to function in Chrome.

The move stems from legitimate technical concerns. A Chromium developer noted that maintaining MV2 support creates substantial tech debt and security vulnerabilities, with several MV2-specific bugs recently discovered. Manifest V3's more restrictive API model fundamentally changes how extensions can intercept and modify network requests, limiting ad blocking capabilities compared to MV2.

Users who rely on traditional ad blockers will need to migrate to Manifest V3-compatible alternatives or switch browsers entirely. While Microsoft Edge and Opera could theoretically maintain MV2 support, they're expected to follow Chrome's lead given their shared Chromium foundation. The transition has been gradual but inevitable.

Chrome 150 arrives later this month with this final flag removal, while remaining MV2 components disappear in version 151. Developers have had years to migrate, yet the ecosystem shakeout will be significant for users who valued granular ad blocking control.