Comment by roelschroeven

That text continues with this:

> We still put a lot of work into making sure that the data that we share with our partners (which we need to do to make Firefox commercially viable) is stripped of any identifying information, or shared only in the aggregate, or is put through our privacy preserving technologies (like OHTTP).

So they share data with partners, which helps to make Firefox commercially viable, meaning those partners pay them for that data. Or in other words, Mozilla sells user data. Even when anonymized or aggregated, it's still selling data.