The new Firefox 75, which recently released, brings a new scheduled task to Windows that allows the collection data, and the information is submitted to Mozilla once a day.
Mozilla pre-announced the change in March 2020, stating that the purpose of this new scheduled task, which is only enabled if users enable it, is to help improve Firefox by "understanding the default browser trends".
Of course, Mozilla says that no personal data is collected, because the company is only interested in “information about current and previous defaults settings of the browser, as well as with the version running on operating system".
Mozilla guarantees that the collected data cannot be associated with any regular profile and once users close it telemetry, the service is automatically disabled.
Of course, as mentioned above, users can stop the service on their own by simply deleting the scheduled task from Windows 10.
"Telemetry data collection is one way we can ensure that we can understand the default browser trends in a way that helps us improve Firefox. "We hope to better understand our users and their choices around browser preferences, so we can continue to build a better Firefox," says Mozilla.
If you want to check the information that Mozilla collects from Firefox, you can open the following internal address:
about: telemetry
This page displays information collected and details that have been stored in the past and have already been submitted to Mozilla.
Mozilla states that it will keep the telemetry data for 13 months "only", after all the information is automatically removed. On the other hand, once you turn off telemetry from Firefox, your data is deleted from Mozilla servers within 30 days.