This is the most critical factor. An app version from 2015 does not have the modern security patches found in today's apps. Logging into your account via an outdated app could expose your data to vulnerabilities that have since been patched in newer versions.
Since modern updates won't install, you must seek "Legacy" versions. The most stable versions for Android 4.2.2 are generally those released between . facebook apk android 4.2.2
Running Facebook on Android 4.2.2 is an exercise in digital archaeology. It is possible to revive the "blue icon" on your vintage Nexus or Galaxy device by sideloading an old APK, but the experience will be severely limited by today's standards. Features will be broken, chats may not work, and security will be compromised. This is the most critical factor
A modified or wrapper APK could intercept Facebook’s network requests and route them through a (running on the same device or local network) that: Since modern updates won't install, you must seek
Before you proceed with installing an old Facebook APK, you must understand the significant risks involved.