Mozilla is on a mission to show that online advertising can be done without violating a user’s privacy—or at least not violating it too much. Next week, the beta channel of Firefox will start testing new advertising tiles based on a user’s browsing history.

The new advertising feature, called Suggested Tiles, joins Directory Tiles and Enhanced Tiles, which went public in Firefox nightly test builds last summer. All three types of tiles appear on a user’s new tab page.

Mozilla says Suggested Tiles will be based on a user’s most “recent and most frequent browsing” in order to deliver more relevant ads. Mozilla believes Suggested Tiles will benefit advertisers since it shows history-based advertising early in the browsing experience when “the user is receptive to hearing from them,” according to a blog post from Dan Herman, Mozilla’s vice president of content services.

Although the ads are based on a user’s browsing history, the decision on which ads to show happens in the browser and not on a third-party server. Only a minimal amount of personal data ever leaves the browser, according to Mozilla, such as click activity and tile pins.

That data is then anonymized before it is used for reports shared with advertisers. You can see a step-by-step breakdown of the process on this infographic on Mozilla’s site.

The story behind the story: Suggested Tiles are the latest in a string of controversial or surprising decisions Mozilla has made to remain relevant and competitive with other browsers. In late 2014, the open source organization closed a deal to make Yahoo the default search provider in Firefox after depending on Google for years. Mozilla also introduced the aforementioned sponsored tiles to remove at least some of its financing dependence on the search deal. Most recently, Mozilla added a default DRM scheme to Firefox to enable HTML 5-based video streaming on popular sites like Netflix.

Tiles, tiles everywhere are tiles

With all these different kinds of tiles on Firefox’s new tab page things might get a little confusing. To review, Directory Tiles are sponsored tiles that appear to new users who have no browsing history. Enhanced Tiles are based on a user’s history and show an improved screenshot image supplied by the site owner. The new image can include a logo as well as a rollover image that appears when you hover your mouse over the tile. Mozilla says Enhanced Tiles would not be displayed to a user unless that site would have already shown up on that user’s new tab page.

Then there’s the new Sponsored Tiles that are ads based on your browsing history, which Mozilla claims put relevant ads in front of potential customers and respects user privacy at the same time.

To start, Suggested Tiles will largely show Mozilla-focused ads promoting things like Firefox for Android and Firefox Marketplace. But that should change as Mozilla signs on more advertising partners.

Anyone who wants to opt-out of the Firefox ad program in the current stable version can do so by clicking the settings cog in the upper right corner of the new tab page. Then select Classic or Blank.