I remember that the introduction of the new WebExtension API to replace the existing extension system was heavily criticized.
The old system gave extensions deep access to the browser and the new extension API (copied over from the Chrome browser) was seen as a limiting dumbing down.
It was a painful transition but very much needed. Now extensions don't clash with one another. The browser code can be modified more freely without impacting extensions and it is possible to implement features such as sandboxing.
It was a painful transition but very much needed. Now extensions don't clash with one another. The browser code can be modified more freely without impacting extensions and it is possible to implement features such as sandboxing.