Mozilla is adding an ad blocker to Firefox Focus 9.0, which is scheduled to be released next month. While some Focus users may currently see ads blocked, this is not being done intentionally, but is more of a byproduct of their tracker blocking.

Firefox Focus is Mozilla's stripped-down light-weight mobile browser for Android and iOS that is designed to enhance a user's privacy by not saving passwords, blocking ad and content trackers, and offering a lean experience without any bells and whistles.

In the current version 8.1 of Firefox Focus, the browser blocks tracking scripts, which will cause some ads to be blocked that require or contain tracking scripts. When BleepingComputer contacted Mozilla to ask about the upcoming ad blocking feature and why some ads are already blocked we were provided the following statement.

"Firefox Focus focuses on blocking trackers. It might also block ads that have these trackers included. Ad blocking is not implemented at the moment."

According to a new Mozilla bug ticket discovered by BleepingComputer, Mozilla plans on adding a full featured ad blocker to Firefox Focus 9.0, which is scheduled to be released on February 12th 2019.

As part of this release, Mozilla will be running an A/B experiment where 50% of the users will have all ad blocking features enabled, while the other 50% will have the ad blocker disabled and its settings hidden from the interface. This experiment is designed to see if enabling ad blocking increases how often the browser is used and the amount of time users spend browsing.

Bug ticket explaining experiment

Unfortunately, not much is known about Firefox Focus' upcoming ad blocking feature and Mozilla told BleepingComputer that they are not sharing any information at this time.

When Focus 9.0 is released, we will provide more coverage on the new ad blocking feature.