Memory leaks are common when running older code on dated hardware. Regularly clear the app cache in your device settings. Alternative Solutions
No official "exclusive" version exists from Meta. However, based on APK archive data, the last stable builds for Android 4.4.2 were: facebook old version apk for android 442 exclusive
After installing, go to the Google Play Store, search for Facebook, tap the three-dot menu, and to prevent it from updating to a newer version automatically. Memory leaks are common when running older code