Chrome extensions Manifest V3 migration tracker
A manifest file is the blueprint of an extension. It includes information such as the extension name, version, logo, and permissions needed to run the extension. Manifest V3 introduces a number of structural changes to how extensions can be loaded in the browser. It is meant to provide "enhancements in security, privacy, and performance". However, critics have called it "deceitful and threatening".
Famous for deprecating before replacement is ready, Manifest V3 is another example of Google trying to force a migration onto an unstable platform. Chrome extension samples show only a small handful of examples written in Manifest V3, while the majority of the API examples are still written in Manifest V2. There are still a lot of bugs in Manifest V3 being discovered and discussed in the Chrome Extensions forum. For extension developers who are trying to build extensions across multiple browsers, this is yet another hurdle to overcome as they will need to make their codes work in Manifest V2 for other browsers until browsers like Firefox and Edge fully support it.
One of the biggest changes in Manifest V3 is the removal of blocking webRequest API support. Google claimed that it is removing that API for "Privacy, Performance, and Compatibility" . Regarding Privacy, Google said that blocking webRequest API "requires excessive access to user data, because extensions need to read each network request made for the user". However, it still allows the the non-blocking webRequest API to be used to observe and analyze traffics. That is, Chrome extensions will still be able to log and collect all your web activities, but an adblocker will have a harder time blocking unwanted ads. Ultimately, this is not about "Privacy". It is more about ad monetization.
The argument about "Performance" is valid, though the benefit is very minor. A well-written Chrome Web Store would add no more than a few milliseconds. Most users will not noticed the performance difference, though they will clearly notice when ads are shown. As for "Compatibility", it is simply to be compatible with "service worker", which is yet another change that is newly introduced in Manifest V3, which has its own set of problems without really giving any noticeable benefit to the users. In certain cases, the unpredictable life-cycles of "service workers" may actually result in worse performances.
To be fair, ChromeStats is able to provide much of the functionality on this site for free thanks to ads. We do not like ads either, and we use adblocker ourselves, though we recognize the financial benefits of showing ads. However, we do not believe that the changes in Manifest V3, as it stands, is well-justified. We are sharing the migration tracker below to help track the current status of Manifest V3 migration.
Overall, Manifest V3 is still poorly adopted by Chrome extension developers. As of today, only 20.27% of all items in Chrome Web Store have migrated to Manifest V3. The rollout of Manifest V3 and deprecation of Manifest V2 has been delayed many times. Please refer to the Chrome's official timeline for when Manifest V2 will stop working.