Mozilla 在 iOS 上也出了自己的 Content Blocker，叫做 Focus by Firefox：「Announcing Focus by Firefox, a Content Blocker for iOS」：
Today we’re pleased to announce the launch of Focus by Firefox, a free content blocker for Safari users on iOS 9 that gives users greater control of their mobile Web experience.
沒搞懂 Mozilla 跑出來弄這個的目的...