Chrome Web Store Set to Purge All Remaining Manifest V2 Extensions on August 31, Leaving Firefox the Last Major Browser Fully Backing uBlock Origin
Google will remove every remaining Manifest V2 extension from the Chrome Web Store on August 31, 2026, completing a phase-out that has already disabled uBlock Origin and other legacy ad blockers in Chrome.
Overview
Google will complete its years-long phase-out of the Manifest V2 extension architecture on August 31, 2026, when it removes every remaining Manifest V2 extension from the Chrome Web Store, according to Chrome for Developers. Extensions already installed on Chrome 138 or earlier will stay on users’ machines but will be unable to receive updates and cannot be reinstalled from the Chrome Web Store once removed, the documentation states. The deadline lands as Firefox has publicly reaffirmed it will keep supporting uBlock Origin, the ad-blocking extension most affected by the shutdown, according to PCWorld.
What We Know
The August 31 date is the final entry in a multi-year timeline Google has published for the Manifest V2 shutdown. According to Chrome for Developers, Chrome first stopped accepting new public and unlisted Manifest V2 submissions to the Web Store in January 2022, followed by private submissions in June 2022. Warning banners began appearing for existing users on the Beta, Dev, and Canary channels on June 3, 2024, and Chrome started disabling installed Manifest V2 extensions in the stable channel starting October 9, 2024. By March 31, 2025, Manifest V2 extensions were disabled by default across all channels, though users could still turn them back on. With Chrome 138 on July 24, 2025, that option disappeared: “With Chrome 138 all users on all channels of Chrome have now Manifest V2 extensions disabled. Users can no longer turn them back on,” per the documentation. Enterprises using the ExtensionManifestV2Availability policy were exempt until the policy itself was scheduled for removal with Chrome 139.
Google has also closed off the workarounds developers and users found to keep Manifest V2 extensions running. According to Android Authority, Chrome developer Devlin Cronin posted a commit to the Chromium project in June 2026 removing the “kExtensionManifestV2Disabled feature,” a flag that had let some users continue installing Manifest V2 extensions. Cronin wrote that “MV2 extensions are no longer allowed in any supported version of Chrome,” citing the complexity and technical debt of maintaining the old architecture, security risks, and MV2-specific bugs the team had found. Android Authority reported that the “Allow legacy extension manifest versions” flag, previously usable as a workaround to sideload extensions like uBlock Origin, was also no longer available in the latest stable version of Chrome as of that report, and that uBlock Origin was no longer installable from the Chrome Web Store even via a direct GitHub link to its store listing.
uBlock Origin is the extension most visibly caught up in the transition, because its full ad- and tracker-blocking approach depends on capabilities Manifest V3 restricts. Firefox has positioned itself as the holdout: according to PCWorld, Mozilla announced via a Bluesky post that “our support for uBlock Origin isn’t going anywhere,” a statement PCWorld reported came in response to news that Microsoft Edge is preparing to lock out uBlock Origin and other Manifest V2 ad blockers as it moves to Manifest V3. PCWorld noted that Edge, like Opera, Brave, Vivaldi, and Samsung Browser, runs on the Chromium engine that Google controls, and that Firefox is one of the few major non-Chromium browsers left — with Safari and DuckDuckGo, the other prominent non-Chromium options, not supporting uBlock Origin either.
For Chrome users who want to keep some ad-blocking functionality, the fallback is uBlock Origin Lite, a Manifest V3-compatible version of the extension. Both PCWorld and Android Authority describe it as offering fewer features and reduced ad-blocking effectiveness compared with the full version. Android Authority also reported that uBlock Origin developer Raymond Hill recommends Firefox on the extension’s GitHub repository and website.
What We Don’t Know
Android Authority’s June 2026 reporting found that Chromium-based Opera and Microsoft Edge still supported uBlock Origin at that time, while noting that “whether they will continue to do so and for how long remains to be seen.” PCWorld’s later report describes Edge as preparing to phase out the extension, but neither source specifies an exact date for when Edge or Opera might drop support entirely, and it is not established whether every Chromium-based browser will follow the same timeline as Chrome itself.
Analysis
The August 31 removal date closes out a shutdown Google has been executing in stages since 2022, but its practical effect is concentrated on a narrower question: which browsers will still let users run extensions with the deep page-access permissions that full-featured ad and tracker blocking has historically required. With Chrome closing off the last installation workarounds and Chromium-based alternatives following Google’s lead, the extension ecosystem is increasingly bifurcating between Manifest V3-only browsers and Firefox, which developer Raymond Hill has pointed users toward directly.