Chrome 150 and 151 Will Finally Kill the Last Ad-Blocker Workarounds

Google is closing the final escape hatches that let old Manifest V2 extensions keep running. For the ad industry, that's not a footnote — it's a structural shift in how many people actually see ads.

Written by Grant Hollis · Bureau Media · Jun 18, 2026

The Last Loopholes Are Closing

Google Chrome is about to finish what it started in 2024. Versions 150 and 151 of Chrome — expected to roll out in late June and July, respectively — will cut off the final technical workarounds that allowed older ad-blocking extensions to keep running after Google officially deprecated support for Manifest V2, the extension architecture that powered tools like uBlock Origin.

This isn't a surprise. Google telegraphed the MV2 sunset well in advance, and the industry spent years arguing about it. But the gap between "officially deprecated" and "actually dead" turned out to be longer than expected, and a portion of Chrome's user base has been running on borrowed time through those workarounds. That time is now up.

What Manifest V2 Actually Was

Without getting lost in the weeds: Manifest V2 was the technical rulebook that Chrome extensions had to follow. Ad blockers built on MV2 could intercept and cancel network requests before they loaded — which is exactly how they blocked ads so effectively.

Manifest V3, Google's replacement framework, restricts that capability. Extensions can still filter content, but the mechanism is more limited. Critics — including the developers of uBlock Origin — have argued that MV3 makes it structurally harder to build a blocker that works as well as the old ones. Google has maintained that MV3 improves security and performance. Both things can be partially true, and the debate has been running for years.

The practical result is that the best-in-class ad blockers either haven't fully migrated to MV3 or have had to ship a meaningfully weaker version of their tools.

What This Means for the Ad Business

Here's the part that matters commercially: Chrome is the dominant browser globally by a significant margin. Every user who was successfully blocking ads on Chrome represents inventory that wasn't being monetized. Some of those users will now migrate to Firefox or another browser that still supports MV2-style blocking. Some will adopt whatever MV3-compatible blocker works best. And some — probably a meaningful slice — will just start seeing ads again.

For publishers who've watched ad-block rates eat into their programmatic revenue for a decade, this is a quiet win. It won't show up as a dramatic spike in any dashboard, but it will show up — gradually, in fill rates and impression counts.

For advertisers, the more interesting question is whether that newly addressable inventory is actually valuable. Users who went out of their way to install and maintain an ad blocker are not, historically, the audience most receptive to display advertising. But reach is reach, and the industry will take it.

The Browser Wars Angle

The users most likely to care about this — technically literate, privacy-conscious, actively hostile to ad tracking — are also the users most likely to switch browsers rather than accept the change. Firefox has been quietly positioning itself as the refuge for exactly this cohort, and browser market share is a slow-moving metric right now, but it does move.

Google is making a calculated bet that most Chrome users won't bother switching. Based on how these transitions have gone historically, they're probably right. But the users who do leave are disproportionately the ones who influence others' browser choices. That's a longer-term brand consideration that doesn't show up in Q3 impression numbers.

Key takeaways

Chrome 150 and 151 (expected late June and July) will eliminate the final workarounds keeping Manifest V2 ad blockers alive in Chrome.
Google phased out MV2 extension support — the architecture behind uBlock Origin and similar tools — in 2024.
Users who stayed on Chrome and kept older blockers running via workarounds will now face a hard choice: switch extensions, switch browsers, or start seeing ads.
For publishers and advertisers, this incrementally expands the addressable audience on Chrome — the world's dominant browser.
The move consolidates Google's Manifest V3 framework as the only path forward for extension developers, which critics argue limits blocking capability by design.

FAQ

Which Chrome versions are removing the ad-blocker workarounds?

Chrome versions 150 and 151, expected in late June and July respectively, will cut off the last remaining workarounds that allowed Manifest V2 ad blockers to keep running.

What is Manifest V2 and why does it matter for ad blocking?

Manifest V2 was the extension framework that allowed ad blockers like uBlock Origin to intercept and block network requests before they loaded — the core mechanism behind effective ad blocking. Google deprecated it in 2024 in favor of Manifest V3, which restricts that capability.

Can users still block ads on Chrome after this change?

Yes, but with more limited tools. Manifest V3-compatible blockers exist, but developers of the most powerful MV2 blockers argue the new framework is structurally less capable. Users who want the strongest blocking will likely need to switch to a browser like Firefox that still supports MV2-style extensions.

What does this mean for publishers and advertisers?

It incrementally expands the pool of Chrome users who can be served ads, since some users who were blocking ads via workarounds will now see them. The effect will be gradual rather than dramatic, and some of those users will migrate to other browsers instead.

Why did Google move from Manifest V2 to Manifest V3?

Google has cited security and performance improvements as the rationale for Manifest V3. Critics, including extension developers, have argued the change also conveniently limits the effectiveness of ad blockers — a product category that competes directly with Google's core advertising business.

Citations

Google Chrome is removing ad blocker loopholesChrome versions 150 and 151, expected in late June and July, will cut off support for the last remaining workarounds for running older ad blockers.
Google Chrome is removing ad blocker loopholesGoogle phased out support for ad-blocking extensions built for Manifest V2, like uBlock Origin, in 2024.
The Verge RSS Feed — Bureau research sourceBureau research source attribution for The Verge coverage of Chrome extension policy changes.