Firefox has extensions available by default on Android. I use Ublock Origin & HTTPS everywhere. I wouldn't call it the "default browser", but it's...Firefox. I

Firefox has extensions available by default on Android. I use Ublock Origin & HTTPS everywhere. I wouldn't call it the "default browser", but it's...Firefox. I wouldn't exactly call it hard either since you just browse to the normal Firefox extension page and click the install button. Google does do everything in its power to prevent me from using Firefox though.