The words used about browser extensions
Terms that turn up on this site, in the Chrome Web Store, and in Chrome's own settings. Kept short, and written for the person affected rather than the person building.
Manifest
A file every extension ships describing what it is, what it needs access to, and which version of the extension platform it targets. It is the most honest thing about an extension: the description is marketing, the manifest is a declaration. Everything on this site's permission sections is read from it.
Manifest V2 and Manifest V3
The two versions of that platform. V2 was the standard for over a decade; V3 replaced it, and Chrome 138 stopped loading V2 extensions in July 2025. An extension still on V2 does not run, whatever its store page suggests. The longer explanation.
Permission
A named capability an extension asks for, such as reading your cookies or your history. Chrome shows the list when you install and again under Details. A permission describes what an extension can do, never what it has done.
Host access
Which sites an extension may read and change. The broadest form is every site you visit; the narrow form names specific addresses. This is usually the most consequential thing in a manifest, and it can be narrowed after installation without uninstalling anything.
Service worker
Where a modern extension's background code runs. It starts when needed and stops afterwards, rather than sitting resident the whole time the browser is open. Extensions on the older platform used a permanent background page instead, which is part of why they cost more memory.
Publisher
Whoever the store lists as responsible for an extension. It can change — extensions with large user bases are bought and sold, and the buyer inherits every permission the seller was granted, without asking you again. We record the publisher on every check so a change shows up.
Removed, delisted, disabled
Three different things. Removed or delisted means the store page is gone: an installed copy keeps working but cannot update or be reinstalled. Disabled means Chrome has switched it off on your machine, which it does for extensions on the retired platform. An extension can also be listed and non-functional at the same time, which is the confusing case this site exists to make visible.
Sunset score
Our own number, 0 to 100, for how close an extension looks to the end of its useful life. It is computed from the manifest, the update date and our own repeated checks, and every page shows which signals produced it. How it is calculated.