For devices stuck on Jelly Bean, the most reliable way to access the platform is through "Lite" versions or web-based alternatives: Facebook Lite
Apps downloaded outside the Play Store carry some risk. Always scan your APK with VirusTotal before installing. Facebook may deprecate Android 4.2.2 support completely by late 2022, so download your "Better" APK now while it still works. facebook apk for android 42 2 better 2021
Facebook APK for Android 2.3.2: The Best “Better” Version for 2021 Facebook APK v42