: This installs the final version built for iOS 12. 💡 Key Features of the iOS 12 Version

: Sign in with your Apple ID on a newer iPhone (iOS 13+) and "Get" the Facebook app. Then, return to your iOS 12.5.5 device; the app will now appear in your Purchased history and allow the "last compatible version" download. Best Features of the iOS 12 Compatible Version

corresponds to a very old Facebook version (likely from 2015–2016). Here's why that's problematic: