https://arstechnica.com/gadgets/2021/02/facebook-makes-the-case-for-activity-tracking-to-ios-14-users-in-new-pop-ups/

Today, Facebook began testing prompts to iPhone and iPad users championing the importance of being tracked by the social network for the benefit of small businesses that use its advertising tools.

The test is in response to Apple's plan to require user opt-in to IDFA (ID for advertisers) tracking across all iOS, iPadOS, and tvOS apps starting with new software updates expected in the spring.