A first look at Firefox's updated Add-ons Manager

The add-ons manager of the Firefox web browser is an essential component; Firefox users may use it to manage installed extensions, themes, and language packs.

Mozilla is in the process of removing anything that is XUL from Firefox. It plans to launch the new about:config in Firefox 67 that uses web standards, and is working on a new version of about:addons as well.

While it is unclear when that new version will be released in Firefox Stable, it is certain that this is going to happen rather sooner than later.

The organization launched an initial redesign of the add-ons manager in October 2018; this initial wave of changes introduced the cards-based design and made some other changes to the interface without removing any functionality from it. Launched in Firefox 64 Stable, it is currently the default view of about:addons. Mozilla revealed back then that the change was part of a larger process.

Part of the redesign landed in recent Firefox Nightly versions already. You need to change the configuration to unlock the new add-ons manager. Note that it is only partially integrated in Firefox Nightly currently and that some functionality is not available; it is okay to get a first impression but not functional enough to use it to manage add-ons.

Load about:config in the Firefox address bar.
Confirm that you will be careful.
Search for extensions.htmlaboutaddons.enable.
Click on the toggle button to set the preference to True.