Link from Schneier to the original article from Proton Mail[0]:

"Some European users who download the new Outlook for Windows will encounter a modal with a troubling disclosure about how Microsoft and several hundred third parties process their data:

"The window informs users that Microsoft and those 801 third parties use their data for a number of purposes, including to:

    Store and/or access information on the user’s device

    Develop and improve products

    Personalize ads and content

    Measure ads and content

    Derive audience insights

    Obtain precise geolocation data

    Identify users through device scanning"

also you get to choose your ads layout.

[0] https://proton.me/blog/outlook-is-microsofts-new-data-collec...