Compatibility guide
Manifest V2 vs Manifest V3: what each Chrome version can install
From Chrome 87 to 156, follow the version line to see when each extension format works, when it fails, and what to check before downloading an older version.
What Manifest V2 and Manifest V3 are
- Manifest V2
- The older Chrome extension format. Extensions run a persistent background page and can intercept and change network requests directly. Chrome is retiring it.
- Manifest V3
- The current format, supported from Chrome 88. The background becomes a service worker that starts on demand, network filtering uses declarative rules (declarativeNetRequest), and permissions are stricter.
Every extension’s manifest.json declares which format it uses; below they are shortened to MV2 and MV3.
Manifest V2 is gone
The browser no longer contains any MV2 switch or policy; every method is refused. MV3 has no upper cutoff — it ran from 88 through 156, the newest we tested. The only remaining risk is a browser that’s too old.
156Newest tested: MV2 refused everywhere, MV3 runs.Measured151All command-line switches gone.Measured
MV2 refused
MV2 is over for ordinary users: installs are refused and can’t be re-enabled; developer mode and “Load unpacked” don’t help. Only enterprise policy (through 138) and command-line switches (through 150) keep it alive.
150Last version where command-line switches work (with an extra re-enable).Measured139Enterprise policy ExtensionManifestV2Availability removed.Measured137MV2 refused by default; it can’t be turned back on.Measured
MV2 turned off by default
MV2 extensions still install, but arrive turned off (unsupportedManifestVersion). The user can turn them back on at chrome://extensions and they run normally. Google rolled this out in stages from October 2024, so some users saw it later.
Oct 2024Google starts the staged rollout to users.Chrome docs129The code default starts turning MV2 off.Measured
Both formats coexist; MV3 fills in
MV2 and MV3 both work — the most forgiving stretch. New MV3 APIs arrive one at a time; an extension using them without declaring a minimum version installs on older browsers, but those features fail.
127–128MV2 still runs; Chrome starts warning about MV2 on the extensions page.Measured120userScripts permission available (the user must also enable it).Chrome docs114sidePanel available.Measured109offscreen API available; earlier versions install and run, but calls fail.MeasuredJan 2022The Chrome Web Store stops accepting new MV2 extensions (store policy, not a browser change).Store policy96declarativeNetRequestWithHostAccess permission available.Chrome docs92ES module backgrounds start running.Measured
MV3 reaches stable
From Chrome 88, MV3 extensions install and run. A background written as an ES module ("type": "module") still installs without ever running until 92.
88–91A module background is listed with a service worker but never starts.Measured88Basic MV3: installs, enables and runs its background.Measured
The MV2-only years
Manifest V2 is the only stable format. An MV3 extension installs and looks enabled in stable Chrome, but its background script never runs — the hardest failure to notice.
87Stable 87 accepts manifest_version 2 at most; service_worker backgrounds are Dev-channel only.Source
From Chrome 137, MV2 is refused and ordinary users have no way around it.
Chrome 129–136 turns MV2 extensions off automatically, but users can still turn them back on.
MV3 needs Chrome 88 or later; older browsers install it but never run it.
Before downloading an older version
- Check the manifest version: on Chrome 137 and later, pick MV3 only.
- Check the minimum version: below it, the install is refused.
- On an old browser, pick the newest compatible version, or update first.
Method and limits
Tested on Oct 18, 2026 on Linux with Chrome for Testing 113–156 and Chromium 87–112 snapshots, using probe extensions and the real Google Translate 2.0.13 / 2.0.18 and AdBlock to separate “installs”, “enabled” and “background actually runs”; the CRX install path was checked with an enterprise force-install. Chrome for Testing has no staged rollouts, so the versions above are when the code takes effect — real users may have seen changes later. Windows, Mac, Edge and other Chromium browsers were not covered. Dates after 150 are estimated from Chrome’s four-week release schedule.
Edge and other Chromium browsers follow their own schedules; they were not tested here.