Manifest V2, V3, and why your extension stopped working
If an extension you relied on stopped working and its store page is still there, this is usually why.
The short version
Every Chrome extension ships a file describing what it is and what it needs. That file declares which version of the extension platform it targets. Manifest V2 was the platform for over a decade; Manifest V3 replaced it. Chrome 138, released in July 2025, stopped loading Manifest V2 extensions, and later releases removed the developer flags that could force one back on. An extension still on V2 does not run on any current Chrome, whatever its store page suggests.
What actually changed
The change people argued about most was network interception. Under V2 an extension with the right permission could watch and rewrite every request your browser made, which is how the most capable content blockers worked. Under V3 an extension declares its rules up front and the browser applies them, so the extension never sees your traffic. That is better for privacy and worse for the blockers that needed the old power — both things are true, which is why the change took years and generated so much heat.
Background code changed too. A V2 extension could keep a page running permanently; a V3 extension gets a service worker that starts when needed and stops afterwards. That is why some extensions feel like they "forget" things after the migration.
If an extension you use is still on V2
- It will not run on current Chrome. If it appears to work, you are on an old version of Chrome, which is its own problem.
- An already-installed copy stays installed but receives no updates, including security fixes.
- Once its listing goes, you cannot reinstall it.
- A rebuilt Manifest V3 version sometimes exists as a separate listing under a similar name. That is worth searching for before you look for a replacement.
Being listed is not being usable
Manifest V2 extensions were reported removed from the Chrome Web Store on 31 August 2026. When we rechecked 290 of them on 2 September, all 290 still had live listings. Their store pages work; the extensions do not. Our Manifest V2 list shows the ones we have found, with what each one asks for and when it was last touched.