Back in February, I wrote about the ad blocker war and Manifest V3 — specifically how Google's MV3 framework wasn't really about security, it was about surgical removal of the capabilities that made ad blocking effective. I said that Chromium-based browsers were the most exposed, and I said Firefox and its hardened forks were in a better position because Mozilla hadn't gone down that road the same way.
Four months later, we're at the end of that road. Chrome 149 shipped on June 2nd, and according to a discussion thread in the w3c WebExtensions Community Group GitHub repo, it's the last version where any of the flag-based workarounds still function. The final flags are being pulled from the codebase now, scheduled to disappear with Chrome 150 (expected June 30) and 151 (July). PCWorld and TechSpot confirmed the timeline this week. "Weeks away, not months" is how TechSpot put it.
Google engineer Devlin Cronin laid it out plainly: MV2 extensions are no longer allowed in any supported version of Chrome, and the code that kept them alive is being treated as unwanted tech debt. The kExtensionManifestV2Disabled feature flag, which controlled MV2 availability and enabled every workaround users and browser makers had been leaning on, is gone from the codebase. What's left:
- Chrome 150 (~June 30):
kExtensionManifestV2Disabledgone — this kills the Windows Registry hack and command-line workarounds - Chrome 151 (July):
ExtensionManifestV2Unsupported,ExtensionManifestV2Availability, andAllowLegacyMV2Extensionsremoved — everything else closes
If you were clinging to any of those escape hatches, you have weeks, not months.
One by One
Chrome was always the obvious one, and anyone still surprised by this hasn't been paying attention. But Edge and Opera are the more interesting part of the story, because both of them made noise at various points about supporting MV2 longer.
Edge already started quietly disabling uBlock Origin and other MV2 extensions back in February. Microsoft didn't throw a press conference about it. They just started doing it.
Opera is the more frustrating case, and honestly the more interesting one. Back in October 2024, they explicitly said they planned to keep MV2 support going — a direct pitch to users fleeing Chrome. Then they quietly sent emails to extension developers telling them to migrate to MV3. The uBlock Origin developer Raymond Hill confirmed he'd received one, saying Opera "plan to abandon MV2-based extensions." Opera's public statement, as of this writing, still says they'll support MV2 "as long as possible." Which is one of those statements that can mean anything depending on how convenient it is. Meanwhile gorhill noted he submitted uBO 1.70.0 to Opera weeks ago and heard nothing back. Draw your own conclusions.
The only Chromium-based browser that remains actually committed is Brave — who put it in writing, naming uBlock Origin, AdGuard, NoScript, and uMatrix as explicitly supported MV2 extensions. And Firefox, as I said in February, is in a genuinely different position. Mozilla explicitly supports both MV2 and MV3, which means uBlock Origin — the real one, not the Lite version — runs fine. Worth noting: gorhill himself has called Firefox the preferred platform for uBO at this point. The developer of the extension is telling you which browser to use.
The Quiet Part, Now Said Out Loud
Cronin's statement in the thread is worth sitting with. He says maintaining MV2 is no longer feasible due to complexity, tech debt, and security risks — and notes that "other browsers can continue supporting these if they so desire." Which is technically true and also a bit rich coming from the company that controls the dominant browser and built the framework that's eliminating the capability.
PCWorld said it more plainly: the fact that this also hobbles ad blockers is "a bonus that Google is unlikely to be too upset about."
This is exactly what I was describing in February under "One More Thing." The MV3 transition wasn't framed as "we're removing your ability to block our ads." It was framed as security and modernization. But look at what actually got cut: the real-time request interception that made effective ad blocking possible. The rest of the framework is largely fine. The part that cost Google money is gone.
I don't need to make that argument anymore. The argument made itself.
Where That Leaves You
If you're still on Chrome and care about blocking ads or trackers, the honest options are:
uBlock Origin Lite is the MV3-native version. It works. It's not as good — the hard caps on filter rules and the lack of dynamic interception are real limitations, not theoretical ones. The developer himself has been clear that uBO Lite is a degraded experience compared to the original.
Switch browsers. Firefox is the most straightforward answer if you want to stay close to what you know. Librewolf is Firefox pre-hardened if you want to skip the manual setup. Brave if you're attached to the Chromium engine and want full uBlock Origin — their Shields implementation lives at the engine level and doesn't need the extension API at all. Vivaldi took a different route: they went MV3 alongside Chromium rather than forking around it, but their answer to the blocker problem is their own built-in Ad and Tracker Blocker — also engine-level, also not dependent on the extension API. It's not quite at Brave Shields or full uBO level yet, but it's solid and improving. Personally I run Vivaldi with uBlock Origin Lite stacked on top of it, plus AdGuard Home doing network-level filtering at the router via my home server setup. No single layer catches everything, but together they cover a lot of ground.
Network-level blocking (Pi-hole, AdGuard Home, NextDNS) still works independently of what the browser allows. It won't help you with server-side ad insertion — Google is moving that direction for YouTube as I described in February, and once an ad is baked into the video stream on Google's servers before it reaches your network, there's nothing to intercept. But for tracker requests, telemetry calls, and a large chunk of ad infrastructure, a network-level blocker still has teeth.
The Pattern Holds
I've written a lot of entries in this series. What strikes me is how consistent the shape of these moves is. A thing that users value gets introduced, maintained long enough to become indispensable, then the removal begins — usually framed as something else, usually incremental, usually with some technical justification that holds together just enough to be not-obviously-cynical.
MV2 wasn't murdered. It was deprecated. For security reasons. Due to complexity. Because of tech debt. The words are different. The outcome is the same: the tool that let you use their platform without fully submitting to it is gone.
I said in February that there's no consumer action that changes this at the platform level — that's still true. But at the individual level, the choices still exist. Firefox exists. Brave exists. Librewolf exists. uBlock Origin itself still exists, fully functional, on all of them. The web is not yet a place where you have no options. It's a place where the largest company in it is actively working to reduce them.
Know the difference. Make your choices accordingly.
Want to talk about big tech's war on users? Find me on Mastodon at @ppb1701@ppb.social