

Under the new proposals, it would use a different API called declarativeNetRequest, which restricts the rules available to the blocking process. One use for this API is to analyze and block traffic sent to advertising networks, making it a popular tool among ad blocking software.

This is the API that extensions use to intercept network requests from the browser. Manifest v3 would restrict the webRequest API, it said. Last November, Google announced changes to the way that it would implement the WebExtensions API as part of Manifest, the system that restricts what extensions can do in Chrome. By supporting the same API as Chrome, Mozilla ensured that extensions written for Chrome could easily port to Firefox. WebExtensions is used in Chromium, the open-source browser project on which Chrome is based, but Mozilla decided to support it too back in August 2015. The WebExtensions interface gives the extensions a way to exchange instructions and information with the browser. WebExtensions is a set of interfaces that browser vendors offer to the developers of extensions, which are programs that extend the browser’s functionality. The Foundation made its announcement on Tuesday in an FAQ updating developers on its plans for the WebExtensions application programming interface (API). Mozilla has told developers not to fret – it won’t follow Google in tweaking its browser to be unfriendly to ad blocking software.
