Firefox will end support for current add-ons at the end of next year

Mozilla will stop supporting add-ons in Firefox next year that don’t work with the WebExtensions api. This will happen from version 57 of the browser. WebExtensions would require less development time and be more compatible with extensions in other browsers.

From April next year, Mozilla will only allow extensions made with the WebExtensions API. After that, users will be able to continue using the old extensions for another six months, but Mozilla says it plans to move to running WebExtensions add-ons exclusively with the release of Firefox 57 on November 28, 2017.

Developers will need to describe current add-ons that do not work with WebExtensions. According to Mozilla, development with WebExtensions is much easier because it is no longer necessary to know exactly how Firefox works. In addition, changes to the browser are less likely or not to block the functionality of add-ons, and developers can use much of the code for add-ons in Chrome, Opera, and other browsers, among others. Mozilla already announced last year that it wanted to switch to the WebExtensions API.