Mozilla added the WebExtensions API to Firefox a few years ago, allowing browser extensions made for Chrome to work on Firefox with minimal (if any) work. Firefox 109 is now rolling out, with a few changes to extension support.
Google started rolling out a new platform for extensions in Chrome at the end of 2020, known as Manifest V3. It’s a significant change to how browser extensions function, with the goal of making them safer and less resource-intensive. Some APIs were removed and replaced with less-powerful alternatives, which affected content blockers like uBlock Origin — sparking some public outage from users and extension developers alike. Last month, Google delayed the timeline for removing older Manifest V2 extensions from the Chrome Web Store.
Firefox 109 is now available, and the main new feature on desktop platforms is initial support for Manifest V3 extensions. That means extensions created for newer versions of Chrome and Microsoft Edge should still work in Firefox, but Mozilla isn’t removing some features, and will continue supporting older extensions for the foreseeable future.
Mozilla said in a blog post, “we agreed to introduce Manifest V3 support for add-ons, maintaining a high level of compatibility to support cross-browser development. However, there are some critical areas — like security and privacy — where our principles call for a different course of action. In a few targeted areas we decided to depart from Chrome’s implementation and incorporate our own distinctively Mozilla elements. Thus Firefox’s version of Manifest V3 will provide cross-browser extension interoperability, along with uniquely improved privacy and security safeguards, and enhanced compatibility for mobile extensions.”
Besides Manifest V3, Firefox 109 on desktop adds keyboard navigation support for HTML date and time input fields, the removal of Colorways, and several security fixes. On Mac, pressing Control/Comand and scrolling a touchpad or mouse wheel now scrolls the page instead of zooming, to match the behavior of other web browsers on macOS.
Firefox 109 for Android isn’t quite as exciting, but there are a few helpful changes. Swiping will no longer activate the address bar in full-screen video mode, there’s now an undo button for removing a pinned site, and search engines now update properly after a language change. There are also a few bug fixes, like an issue that was affecting video calls using the H.264 video codec.
Firefox 109 is slowly rolling out to Windows, macOS, Linux, and Android — if you don’t have it yet, you should get it soon. You can download Firefox from Mozilla’s official website, the Google Play Store, Apple App Store, and Microsoft Store.