"For the first time, you can share your location to an app just once and then require it to ask you again next time it wants it", Craig Federighi, Apple's senior vice president of software engineering, said when the update was announced. Apple released iOS 13.1 Developer Beta 3 after their Special event. "If you do choose to grant an app the ability to continually monitor your location in the background, we'll give you reports so you'll know what they're up to".
The rather blunt blog post by Facebook explains some of the ways users might benefit when allowing Facebook to track their location, including the background when not actively using the Facebook application. It is also being perceived as a clarification on Facebook's part about how it uses user location data.
Facebook's most up-to-date blog article advises users how iOS 13 will alter place sharing on the program. But, to mitigate this issue, Facebook will be going by the setting that users have enabled for its app on Facebook background location settings, instead going by the setting enabled on the device. The home screen has been slightly changed so you can see more apps and pin widgets to it.