Mozilla will soon remove its Adjust telemetry service from the Android and iOS versions of the Firefox and Firefox Focus browsers. Apparently, the developer collected data on the effectiveness of Firefox advertising campaigns without disclosing this.

Mozilla, the developer of Firefox, until recently used the Adjust telemetry service to collect data from its Firefox and Firefox Focus apps for Android and iOS. Through this service, the company collected data on the number of installations of these specific apps following Mozilla’s advertising campaigns.

Not informed

Mozilla observer Sören Hentzschel points out that the release notes do not indicate that this service collects data. This means that end users were not aware that the service forwards data to Mozilla, which remarkable for a browser provider that claims to value (data) privacy.

Mozilla’s removal of Adjust may also have been the reason why the Marketing Data option was removed from the Firefox app for Android.

Previous data protection complaints

The company’s actions could also be a result of previous complaints about the default enablement of “privacy-protecting advertising metrics” in Firefox. This option has been enabled by default since the release of Firefox 128 on July 9.

The service collects data on how users respond to ads and shares this data with advertisers in an aggregate form, but users can opt out of this option.

Mozilla regrets that this telemetry has been enabled, but defends the reason why it is enabled by default. According to the browser provider, the advertisers’ desiThe temptation to obtain information about the effectiveness of their campaigns is difficult to avoid.

Mozilla wants to solve this problem in the most user-friendly way possible. Currently, the feature is only available for test sites and Firefox users.

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