The new Firefox 75, which recently released, brings a new scheduled task to Windows that allows the data collection, 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 program's default trends browsing".
Of course, Mozilla states that no personal data is collected, because the company is only interested in “information about the current and previous default settings of the browser, as well as 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 says it will retain telemetry data for "only" 13 months, after all information is automatically removed. On the other hand, once you disable telemetry from Firefox, your data is deleted within 30 days of it servers Mozilla.