Almost everyone misunderstands Chrome extension manifest version 3

Almost everyone misunderstands Chrome extension manifest version 3, the successor to Chrome extension manifest version 2, MV3 and MV2 for short. As a professional web browser extension developer, I had to migrate my Chrome extensions from MV2 to MV3, which forced me to learn the difference. In this blog post, I hope to dispel the common misunderstanding. The reason almost everyone misunderstands MV3 is that they mistakenly equate the extension manifest version with the content blocking API, used for blocking ads on the web. There are three main types of web browser extension content blocking API: Blocking webRequest DeclarativeNetRequest Safari content blocker The blocking webRequest API is based on JavaScript, whereas the declarativeNetRequest and Safari content blocker API are both rule-based: the extension declares a set of rules to block content, and those rules are applied to URL requests by the web browser itself rather than by the web browser extension. The Safari content…