Mozilla Drops Spy Function from Firefox Under Pressure

Mozilla has decided to delete the integration with Adjust from its Firefox Klar browsers (Firefox Focus) for both Android and iOS. The SDK Adjust was previously used to measure the effectiveness of marketing campaigns, allowing Mozilla to track whether the browser was installed after advertising. The data used for analysis was collected through Adjust servers based in Germany.

The removal of Adjust was due to concerns regarding the collection of data on the effectiveness of Firefox advertising campaigns without proper user notification. This led to the disappearance of the “Marketing Data” option in the data collection settings of Firefox for Android. This option, which had been included by default since July 2023, allowed for the collection of user reaction data to advertising, which was then shared with advertisers in an aggregated format. While users had the option to disable this function, its activation without clear consent sparked a negative response.

Mozilla has commented on the implementation of such telemetry, explaining that it is enabled by default due to advertiser demands for campaign effectiveness data. The company highlighted the challenge of balancing user privacy and advertisers’ needs for information.

Adjust has been disabled in versions Firefox 129.0.2 for Android and 129.2 for iOS by Mozilla.

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