Common ad requests
The built in filter list blocks many known ad requests while pages load.
Features
Ad Cleanser pairs ad blocking with clear site exceptions and a new tab you can make your own.
Browsing
Blocking starts as pages load. When a site needs a different choice, the toolbar keeps that change close.
The built in filter list blocks many known ad requests while pages load.
Page styling hides many ad containers early so blank areas are less likely to linger.
Extra page handling helps reduce some ad interruptions on supported video pages.
Exceptions
A full site exception works across that domain. A page exception stays limited to the exact address you save.
New tab
The Ad Cleanser new tab combines web search, shortcut tiles, and story shelves. Personalize controls let you show less or more.

Your browser, your choice
If Firefox asks about the extension search provider, you can accept it or keep your current search setting. You can review browser search settings later as well.
The FAQ covers blocking, exceptions, search, and removal.