Absolutely. Everything is encrypted and we fully anonymize the data—even we do not know who is who. Our guiding principle is that we treat your data the same way we would want our own to be treated. That's the high-level principle — to be clear, don't do things without consent, and never do things you wouldn't want done with your own data.

The implementation gets technical, but we describe it in detail in our privacy and security page. The Mozilla Foundation also did their own review here.