If the app isn't in your "Purchased" list, the App Store won't offer an older version. You can fix this by temporarily using a newer device: Borrow a newer iPhone/iPad (running iOS 13.4+) and sign in with your Apple ID
Tap the (the square icon with an upward arrow) at the bottom of the screen. Scroll down and select Add to Home Screen . Name the shortcut "Facebook" and tap Add . facebook old version for ios 1255 install
How to Install an Old Version of Facebook on iOS 12.5.5 (iPhone 6/5S/iPad Mini) If the app isn't in your "Purchased" list,
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