Mozilla expects to launch Manifest V3 extension support in Firefox in late 2022
Mozilla plans to introduce support for Manifest V3 extensions in the organization’s Firefox web browser in late 2022. Preview versions are already available in development editions of the web browser.
While Mozilla plans to introduce support for Manifest V3 in Firefox, it will not remove support for APIs that are essential for privacy extensions. Content blockers and other privacy extensions will continue to work in Firefox as before, as long as the developers continue to support them.
Manifest V3 defines the APIs and capabilities of browser extensions. Google announced the new version of the manifest in early 2019 and revealed that Chrome extensions would eventually need to be updated to remain available to Chrome browser users.
The initial version of the draft was controversially discussed. The developers expressed concern that some of the planned changes would limit the proper functioning of privacy-focused extensions such as content blockers. Google made some concessions to developers, but continued its work to introduce new capabilities and remove old ones. The company got Manifest V3 support in Chrome Canary 80 and in Chrome Beta 88.
Firefox extensions will not be limited by Manifest V3
Mozilla announced in 2019 that it would implement support for Manifest V3 in Firefox but would make adjustments to certain limitations. A new blog post on the Mozilla Add-ons Community Blog sheds light on adoption and the differences between Mozilla’s and Google’s implementation.
The decision to remove the blocking part of the WebRequest API and replace it with the limiting declarative NetRequest API was at the center of the controversy. Mozilla notes that the new API limits “the capabilities of certain types of privacy extensions without a proper replacement.”
Mozilla will maintain the WebRequest API in Firefox to ensure that privacy extensions don’t just provide the functionality they were designed to do. The organization will implement the NetRequest declarative API for compatibility reasons according to the blog post.
Mozilla “will continue to work with content blockers and other key consumers of this API to identify current and future alternatives where appropriate.”
Firefox will also support event pages in Manifest V3 and will introduce support for Service Workers in future releases.
Developers can enable preview in the following ways in current development editions of the browser:
- Load about:config in the address bar of the web browser.
- Confirm that you will be careful.
- Look for extensions.manifestV3.enabled and set the preference to TRUE with a click of the switch.
- Search for xpinstall.signatures.required and set the preference to FALSE.
- Reinicie Firefox.
Extensions can then be installed via about:debugging. Permanent installation of the Manifest V3 extensions is possible in the Nightly and Developer editions of the Firefox web browser. The implementation is not complete at the time of this writing.
Now you: What is your opinion on Mozilla’s decision?