I'd like feature parity w/ Firefox for desktops or Firefox for Android, but I have no idea how realistic that is. How realistic is it? Also, can you implement

I'd like feature parity w/ Firefox for desktops or Firefox for Android, but I have no idea how realistic that is. How realistic is it? Also, can you implement the WebExtensions API? That would be a big boost, enabling all the features in FF add-ons.